{"id":712,"date":"2024-07-01T13:47:02","date_gmt":"2024-07-01T05:47:02","guid":{"rendered":"https:\/\/levin.ink\/?p=712"},"modified":"2024-07-02T15:31:23","modified_gmt":"2024-07-02T07:31:23","slug":"js-3-18-%e7%bd%91%e7%bb%9c%e8%af%b7%e6%b1%82","status":"publish","type":"post","link":"https:\/\/levin.ink\/?p=712","title":{"rendered":"JS &#8211; 3-18 \u7f51\u7edc\u8bf7\u6c42"},"content":{"rendered":"<h1>Fetch<\/h1>\n<p>JavaScript \u53ef\u4ee5\u5c06\u7f51\u7edc\u8bf7\u6c42\u53d1\u9001\u5230\u670d\u52a1\u5668\uff0c\u5e76\u5728\u9700\u8981\u65f6\u52a0\u8f7d\u65b0\u4fe1\u606f\u3002<br \/>\n\u4f8b\u5982\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u7f51\u7edc\u8bf7\u6c42\u6765\uff1a<\/p>\n<ul>\n<li>\u63d0\u4ea4\u8ba2\u5355\uff0c<\/li>\n<li>\u52a0\u8f7d\u7528\u6237\u4fe1\u606f\uff0c<\/li>\n<li>\u4ece\u670d\u52a1\u5668\u63a5\u6536\u6700\u65b0\u7684\u66f4\u65b0\uff0c<\/li>\n<li>\u2026\u2026\u7b49\u3002<br \/>\n\u2026\u2026\u6240\u6709\u8fd9\u4e9b\u90fd\u6ca1\u6709\u91cd\u65b0\u52a0\u8f7d\u9875\u9762\uff01<br \/>\n\u5bf9\u4e8e\u6765\u81ea JavaScript \u7684\u7f51\u7edc\u8bf7\u6c42\uff0c\u6709\u4e00\u4e2a\u603b\u79f0\u672f\u8bed \u201cAJAX\u201d\uff08<strong>A<\/strong>synchronous\u00a0<strong>J<\/strong>avaScript\u00a0<strong>A<\/strong>nd\u00a0<strong>X<\/strong>ML \u7684\u7b80\u79f0\uff09\u3002\u4f46\u662f\uff0c\u6211\u4eec\u4e0d\u5fc5\u4f7f\u7528 XML\uff1a\u8fd9\u4e2a\u672f\u8bed\u8bde\u751f\u4e8e\u5f88\u4e45\u4ee5\u524d\uff0c\u6240\u4ee5\u8fd9\u4e2a\u8bcd\u4e00\u76f4\u5728\u90a3\u513f\u3002<br \/>\n\u6709\u5f88\u591a\u65b9\u5f0f\u53ef\u4ee5\u5411\u670d\u52a1\u5668\u53d1\u9001\u7f51\u7edc\u8bf7\u6c42\uff0c\u5e76\u4ece\u670d\u52a1\u5668\u83b7\u53d6\u4fe1\u606f\u3002<br \/>\n<code>fetch()<\/code>\u00a0\u65b9\u6cd5\u662f\u4e00\u79cd\u73b0\u4ee3\u901a\u7528\u7684\u65b9\u6cd5\uff0c\u90a3\u4e48\u6211\u4eec\u5c31\u4ece\u5b83\u5f00\u59cb\u5427\u3002\u65e7\u7248\u672c\u7684\u6d4f\u89c8\u5668\u4e0d\u652f\u6301\u5b83\uff08\u53ef\u4ee5 polyfill\uff09\uff0c\u4f46\u662f\u5b83\u5728\u73b0\u4ee3\u6d4f\u89c8\u5668\u4e2d\u7684\u652f\u6301\u60c5\u51b5\u5f88\u597d\u3002<br \/>\n\u57fa\u672c\u8bed\u6cd5\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let promise = fetch(url, [options])\n<\/code><\/pre>\n<ul>\n<li><strong><code>url<\/code><\/strong>\u00a0\u2014\u2014 \u8981\u8bbf\u95ee\u7684 URL\u3002<\/li>\n<li><strong><code>options<\/code><\/strong>\u00a0\u2014\u2014 \u53ef\u9009\u53c2\u6570\uff1amethod\uff0cheader \u7b49\u3002<br \/>\n\u6ca1\u6709\u00a0<code>options<\/code>\uff0c\u8fd9\u5c31\u662f\u4e00\u4e2a\u7b80\u5355\u7684 GET \u8bf7\u6c42\uff0c\u4e0b\u8f7d\u00a0<code>url<\/code>\u00a0\u7684\u5185\u5bb9\u3002<br \/>\n\u6d4f\u89c8\u5668\u7acb\u5373\u542f\u52a8\u8bf7\u6c42\uff0c\u5e76\u8fd4\u56de\u4e00\u4e2a\u8be5\u8c03\u7528\u4ee3\u7801\u5e94\u8be5\u7528\u6765\u83b7\u53d6\u7ed3\u679c\u7684\u00a0<code>promise<\/code>\u3002<br \/>\n\u83b7\u53d6\u54cd\u5e94\u901a\u5e38\u9700\u8981\u7ecf\u8fc7\u4e24\u4e2a\u9636\u6bb5\u3002<br \/>\n<strong>\u7b2c\u4e00\u9636\u6bb5\uff0c\u5f53\u670d\u52a1\u5668\u53d1\u9001\u4e86\u54cd\u5e94\u5934\uff08response header\uff09\uff0c<code>fetch<\/code>\u00a0\u8fd4\u56de\u7684\u00a0<code>promise<\/code>\u00a0\u5c31\u4f7f\u7528\u5185\u5efa\u7684\u00a0<a href=\"https:\/\/fetch.spec.whatwg.org\/#response-class\">Response<\/a>\u00a0class \u5bf9\u8c61\u6765\u5bf9\u54cd\u5e94\u5934\u8fdb\u884c\u89e3\u6790\u3002<\/strong><br \/>\n\u5728\u8fd9\u4e2a\u9636\u6bb5\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u68c0\u67e5\u54cd\u5e94\u5934\uff0c\u6765\u68c0\u67e5 HTTP \u72b6\u6001\u4ee5\u786e\u5b9a\u8bf7\u6c42\u662f\u5426\u6210\u529f\uff0c\u5f53\u524d\u8fd8\u6ca1\u6709\u54cd\u5e94\u4f53\uff08response body\uff09\u3002<br \/>\n\u5982\u679c\u00a0<code>fetch<\/code>\u00a0\u65e0\u6cd5\u5efa\u7acb\u4e00\u4e2a HTTP \u8bf7\u6c42\uff0c\u4f8b\u5982\u7f51\u7edc\u95ee\u9898\uff0c\u4ea6\u6216\u662f\u8bf7\u6c42\u7684\u7f51\u5740\u4e0d\u5b58\u5728\uff0c\u90a3\u4e48 promise \u5c31\u4f1a reject\u3002\u5f02\u5e38\u7684 HTTP \u72b6\u6001\uff0c\u4f8b\u5982 404 \u6216 500\uff0c\u4e0d\u4f1a\u5bfc\u81f4\u51fa\u73b0 error\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u5728 response \u7684\u5c5e\u6027\u4e2d\u770b\u5230 HTTP \u72b6\u6001\uff1a<\/li>\n<li><strong><code>status<\/code><\/strong>\u00a0\u2014\u2014 HTTP \u72b6\u6001\u7801\uff0c\u4f8b\u5982 200\u3002<\/li>\n<li><strong><code>ok<\/code><\/strong>\u00a0\u2014\u2014 \u5e03\u5c14\u503c\uff0c\u5982\u679c HTTP \u72b6\u6001\u7801\u4e3a 200-299\uff0c\u5219\u4e3a\u00a0<code>true<\/code>\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let response = await fetch(url);\n\nif (response.ok) { \/\/ \u5982\u679c HTTP \u72b6\u6001\u7801\u4e3a 200-299\n  \/\/ \u83b7\u53d6 response body\uff08\u6b64\u65b9\u6cd5\u4f1a\u5728\u4e0b\u9762\u89e3\u91ca\uff09\n  let json = await response.json();\n} else {\n  alert(&quot;HTTP-Error: &quot; + response.status);\n}\n<\/code><\/pre>\n<p><strong>\u7b2c\u4e8c\u9636\u6bb5\uff0c\u4e3a\u4e86\u83b7\u53d6 response body\uff0c\u6211\u4eec\u9700\u8981\u4f7f\u7528\u4e00\u4e2a\u5176\u4ed6\u7684\u65b9\u6cd5\u8c03\u7528\u3002<\/strong><br \/>\n<code>Response<\/code>\u00a0\u63d0\u4f9b\u4e86\u591a\u79cd\u57fa\u4e8e promise \u7684\u65b9\u6cd5\uff0c\u6765\u4ee5\u4e0d\u540c\u7684\u683c\u5f0f\u8bbf\u95ee body\uff1a<\/p>\n<ul>\n<li><strong><code>response.text()<\/code><\/strong>\u00a0\u2014\u2014 \u8bfb\u53d6 response\uff0c\u5e76\u4ee5\u6587\u672c\u5f62\u5f0f\u8fd4\u56de response\uff0c<\/li>\n<li><strong><code>response.json()<\/code><\/strong>\u00a0\u2014\u2014 \u5c06 response \u89e3\u6790\u4e3a JSON \u683c\u5f0f\uff0c<\/li>\n<li><strong><code>response.formData()<\/code><\/strong>\u00a0\u2014\u2014 \u4ee5\u00a0<code>FormData<\/code>\u00a0\u5bf9\u8c61\uff08\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/formdata\">\u4e0b\u4e00\u7ae0<\/a>\u00a0\u6709\u89e3\u91ca\uff09\u7684\u5f62\u5f0f\u8fd4\u56de response\uff0c<\/li>\n<li><strong><code>response.blob()<\/code><\/strong>\u00a0\u2014\u2014 \u4ee5\u00a0<a href=\"https:\/\/zh.javascript.info\/blob\">Blob<\/a>\uff08\u5177\u6709\u7c7b\u578b\u7684\u4e8c\u8fdb\u5236\u6570\u636e\uff09\u5f62\u5f0f\u8fd4\u56de response\uff0c<\/li>\n<li><strong><code>response.arrayBuffer()<\/code><\/strong>\u00a0\u2014\u2014 \u4ee5\u00a0<a href=\"https:\/\/zh.javascript.info\/arraybuffer-binary-arrays\">ArrayBuffer<\/a>\uff08\u4f4e\u7ea7\u522b\u7684\u4e8c\u8fdb\u5236\u6570\u636e\uff09\u5f62\u5f0f\u8fd4\u56de response\uff0c<\/li>\n<li>\u53e6\u5916\uff0c<code>response.body<\/code>\u00a0\u662f\u00a0<a href=\"https:\/\/streams.spec.whatwg.org\/#rs-class\">ReadableStream<\/a>\u00a0\u5bf9\u8c61\uff0c\u5b83\u5141\u8bb8\u4f60\u9010\u5757\u8bfb\u53d6 body\uff0c\u6211\u4eec\u7a0d\u540e\u4f1a\u7528\u4e00\u4e2a\u4f8b\u5b50\u89e3\u91ca\u5b83\u3002<br \/>\n\u4f8b\u5982\uff0c\u6211\u4eec\u4ece GitHub \u83b7\u53d6\u6700\u65b0 commits \u7684 JSON \u5bf9\u8c61\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let url = 'https:\/\/api.github.com\/repos\/javascript-tutorial\/en.javascript.info\/commits';\nlet response = await fetch(url);\n\nlet commits = await response.json(); \/\/ \u8bfb\u53d6 response body\uff0c\u5e76\u5c06\u5176\u89e3\u6790\u4e3a JSON \u683c\u5f0f\n\nalert(commits[0].author.login);\n<\/code><\/pre>\n<p>\u4e5f\u53ef\u4ee5\u4f7f\u7528\u7eaf promise \u8bed\u6cd5\uff0c\u4e0d\u4f7f\u7528\u00a0<code>await<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">fetch('https:\/\/api.github.com\/repos\/javascript-tutorial\/en.javascript.info\/commits')\n  .then(response =&gt; response.json())\n  .then(commits =&gt; alert(commits[0].author.login));\n<\/code><\/pre>\n<p>\u8981\u83b7\u53d6\u54cd\u5e94\u6587\u672c\uff0c\u53ef\u4ee5\u4f7f\u7528\u00a0<code>await response.text()<\/code>\u00a0\u4ee3\u66ff\u00a0<code>.json()<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">let response = await fetch('https:\/\/api.github.com\/repos\/javascript-tutorial\/en.javascript.info\/commits');\n\nlet text = await response.text(); \/\/ \u5c06 response body \u8bfb\u53d6\u4e3a\u6587\u672c\n\nalert(text.slice(0, 80) + '...');\n<\/code><\/pre>\n<p>\u4f5c\u4e3a\u4e00\u4e2a\u8bfb\u53d6\u4e3a\u4e8c\u8fdb\u5236\u683c\u5f0f\u7684\u6f14\u793a\u793a\u4f8b\uff0c\u8ba9\u6211\u4eec fetch \u5e76\u663e\u793a\u4e00\u5f20\u00a0<a href=\"https:\/\/fetch.spec.whatwg.org\/\">\u201cfetch\u201d \u89c4\u8303<\/a>\u00a0\u4e2d\u7684\u56fe\u7247\uff08<code>Blob<\/code>\u00a0\u64cd\u4f5c\u7684\u6709\u5173\u5185\u5bb9\u8bf7\u89c1\u00a0<a href=\"https:\/\/zh.javascript.info\/blob\">Blob<\/a>\uff09\uff1a<\/p>\n<pre><code class=\"language-js\">let response = await fetch('\/article\/fetch\/logo-fetch.svg');\n\nlet blob = await response.blob(); \/\/ \u4e0b\u8f7d\u4e3a Blob \u5bf9\u8c61\n\n\/\/ \u4e3a\u5176\u521b\u5efa\u4e00\u4e2a &lt;img&gt;\nlet img = document.createElement('img');\nimg.style = 'position:fixed;top:10px;left:10px;width:100px';\ndocument.body.append(img);\n\n\/\/ \u663e\u793a\u5b83\nimg.src = URL.createObjectURL(blob);\n\nsetTimeout(() =&gt; { \/\/ 3 \u79d2\u540e\u5c06\u5176\u9690\u85cf\n  img.remove();\n  URL.revokeObjectURL(img.src);\n}, 3000);\n<\/code><\/pre>\n<blockquote>\n<p>\u91cd\u8981\uff1a<br \/>\n\u6211\u4eec\u53ea\u80fd\u9009\u62e9\u4e00\u79cd\u8bfb\u53d6 body \u7684\u65b9\u6cd5\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u5df2\u7ecf\u4f7f\u7528\u4e86\u00a0<code>response.text()<\/code>\u00a0\u65b9\u6cd5\u6765\u83b7\u53d6 response\uff0c\u90a3\u4e48\u5982\u679c\u518d\u7528\u00a0<code>response.json()<\/code>\uff0c\u5219\u4e0d\u4f1a\u751f\u6548\uff0c\u56e0\u4e3a body \u5185\u5bb9\u5df2\u7ecf\u88ab\u5904\u7406\u8fc7\u4e86\u3002<\/p>\n<\/blockquote>\n<pre><code class=\"language-js\">let text = await response.text(); \/\/ response body \u88ab\u5904\u7406\u4e86\nlet parsed = await response.json(); \/\/ \u5931\u8d25\uff08\u5df2\u7ecf\u88ab\u5904\u7406\u8fc7\u4e86\uff09\n<\/code><\/pre>\n<h2>Response header<\/h2>\n<p>Response header \u4f4d\u4e8e\u00a0<code>response.headers<\/code>\u00a0\u4e2d\u7684\u4e00\u4e2a\u7c7b\u4f3c\u4e8e Map \u7684 header \u5bf9\u8c61\u3002<br \/>\n\u5b83\u4e0d\u662f\u771f\u6b63\u7684 Map\uff0c\u4f46\u662f\u5b83\u5177\u6709\u7c7b\u4f3c\u7684\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u6309\u540d\u79f0\uff08name\uff09\u83b7\u53d6\u5404\u4e2a header\uff0c\u6216\u8fed\u4ee3\u5b83\u4eec\uff1a<\/p>\n<pre><code class=\"language-js\">let response = await fetch('https:\/\/api.github.com\/repos\/javascript-tutorial\/en.javascript.info\/commits');\n\n\/\/ \u83b7\u53d6\u4e00\u4e2a header\nalert(response.headers.get('Content-Type')); \/\/ application\/json; charset=utf-8\n\n\/\/ \u8fed\u4ee3\u6240\u6709 header\nfor (let [key, value] of response.headers) {\n  alert(`${key} = ${value}`);\n}\n<\/code><\/pre>\n<h2>Request header<\/h2>\n<p>\u8981\u5728\u00a0<code>fetch<\/code>\u00a0\u4e2d\u8bbe\u7f6e request header\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>headers<\/code>\u00a0\u9009\u9879\u3002\u5b83\u6709\u4e00\u4e2a\u5e26\u6709\u8f93\u51fa header \u7684\u5bf9\u8c61\uff0c\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<pre><code class=\"language-js\">let response = fetch(protectedUrl, {\n  headers: {\n    Authentication: 'secret'\n  }\n});\n<\/code><\/pre>\n<p>\u2026\u2026\u4f46\u662f\u6709\u4e00\u4e9b\u6211\u4eec\u65e0\u6cd5\u8bbe\u7f6e\u7684 header\uff08\u8be6\u89c1\u00a0<a href=\"https:\/\/fetch.spec.whatwg.org\/#forbidden-header-name\">forbidden HTTP headers<\/a>\uff09\uff1a<\/p>\n<ul>\n<li><code>Accept-Charset<\/code>,\u00a0<code>Accept-Encoding<\/code><\/li>\n<li><code>Access-Control-Request-Headers<\/code><\/li>\n<li><code>Access-Control-Request-Method<\/code><\/li>\n<li><code>Connection<\/code><\/li>\n<li><code>Content-Length<\/code><\/li>\n<li><code>Cookie<\/code>,\u00a0<code>Cookie2<\/code><\/li>\n<li><code>Date<\/code><\/li>\n<li><code>DNT<\/code><\/li>\n<li><code>Expect<\/code><\/li>\n<li><code>Host<\/code><\/li>\n<li><code>Keep-Alive<\/code><\/li>\n<li><code>Origin<\/code><\/li>\n<li><code>Referer<\/code><\/li>\n<li><code>TE<\/code><\/li>\n<li><code>Trailer<\/code><\/li>\n<li><code>Transfer-Encoding<\/code><\/li>\n<li><code>Upgrade<\/code><\/li>\n<li><code>Via<\/code><\/li>\n<li><code>Proxy-*<\/code><\/li>\n<li><code>Sec-*<\/code><br \/>\n\u8fd9\u4e9b header \u4fdd\u8bc1\u4e86 HTTP \u7684\u6b63\u786e\u6027\u548c\u5b89\u5168\u6027\uff0c\u6240\u4ee5\u5b83\u4eec\u4ec5\u7531\u6d4f\u89c8\u5668\u63a7\u5236\u3002<\/li>\n<\/ul>\n<h2>POST \u8bf7\u6c42<\/h2>\n<p>\u8981\u521b\u5efa\u4e00\u4e2a\u00a0<code>POST<\/code>\u00a0\u8bf7\u6c42\uff0c\u6216\u8005\u5176\u4ed6\u65b9\u6cd5\u7684\u8bf7\u6c42\uff0c\u6211\u4eec\u9700\u8981\u4f7f\u7528\u00a0<code>fetch<\/code>\u00a0\u9009\u9879\uff1a<\/p>\n<ul>\n<li><strong><code>method<\/code><\/strong>\u00a0\u2014\u2014 HTTP \u65b9\u6cd5\uff0c\u4f8b\u5982\u00a0<code>POST<\/code>\uff0c<\/li>\n<li><strong><code>body<\/code><\/strong>\u00a0\u2014\u2014 request body\uff0c\u5176\u4e2d\u4e4b\u4e00\uff1a\n<ul>\n<li>\u5b57\u7b26\u4e32\uff08\u4f8b\u5982 JSON \u7f16\u7801\u7684\uff09\uff0c<\/li>\n<li><code>FormData<\/code>\u00a0\u5bf9\u8c61\uff0c\u4ee5\u00a0<code>multipart\/form-data<\/code>\u00a0\u5f62\u5f0f\u53d1\u9001\u6570\u636e\uff0c<\/li>\n<li><code>Blob<\/code>\/<code>BufferSource<\/code>\u00a0\u53d1\u9001\u4e8c\u8fdb\u5236\u6570\u636e\uff0c<\/li>\n<li><a href=\"https:\/\/zh.javascript.info\/url\">URLSearchParams<\/a>\uff0c\u4ee5\u00a0<code>x-www-form-urlencoded<\/code>\u00a0\u7f16\u7801\u5f62\u5f0f\u53d1\u9001\u6570\u636e\uff0c\u5f88\u5c11\u4f7f\u7528\u3002<br \/>\nJSON \u5f62\u5f0f\u662f\u6700\u5e38\u7528\u7684\u3002<br \/>\n\u4f8b\u5982\uff0c\u4e0b\u9762\u8fd9\u6bb5\u4ee3\u7801\u4ee5 JSON \u5f62\u5f0f\u53d1\u9001\u00a0<code>user<\/code>\u00a0\u5bf9\u8c61\uff1a<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let user = {\n  name: 'John',\n  surname: 'Smith'\n};\n\nlet response = await fetch('\/article\/fetch\/post\/user', {\n  method: 'POST',\n  headers: {\n    'Content-Type': 'application\/json;charset=utf-8'\n  },\n  body: JSON.stringify(user)\n});\n\nlet result = await response.json();\nalert(result.message);\n<\/code><\/pre>\n<p>\u8bf7\u6ce8\u610f\uff0c\u5982\u679c\u8bf7\u6c42\u7684\u00a0<code>body<\/code>\u00a0\u662f\u5b57\u7b26\u4e32\uff0c\u5219\u00a0<code>Content-Type<\/code>\u00a0\u4f1a\u9ed8\u8ba4\u8bbe\u7f6e\u4e3a\u00a0<code>text\/plain;charset=UTF-8<\/code>\u3002<br \/>\n\u4f46\u662f\uff0c\u5f53\u6211\u4eec\u8981\u53d1\u9001 JSON \u65f6\uff0c\u6211\u4eec\u4f1a\u4f7f\u7528\u00a0<code>headers<\/code>\u00a0\u9009\u9879\u6765\u53d1\u9001\u00a0<code>application\/json<\/code>\uff0c\u8fd9\u662f JSON \u7f16\u7801\u7684\u6570\u636e\u7684\u6b63\u786e\u7684\u00a0<code>Content-Type<\/code>\u3002<\/p>\n<h2>\u53d1\u9001\u56fe\u7247<\/h2>\n<p>\u6211\u4eec\u540c\u6837\u53ef\u4ee5\u4f7f\u7528\u00a0<code>Blob<\/code>\u00a0\u6216\u00a0<code>BufferSource<\/code>\u00a0\u5bf9\u8c61\u901a\u8fc7\u00a0<code>fetch<\/code>\u00a0\u63d0\u4ea4\u4e8c\u8fdb\u5236\u6570\u636e\u3002<br \/>\n\u4f8b\u5982\uff0c\u8fd9\u91cc\u6709\u4e00\u4e2a\u00a0<code>&lt;canvas&gt;<\/code>\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5728\u5176\u4e0a\u79fb\u52a8\u9f20\u6807\u6765\u8fdb\u884c\u7ed8\u5236\u3002\u70b9\u51fb \u201csubmit\u201d \u6309\u94ae\u5c06\u56fe\u7247\u53d1\u9001\u5230\u670d\u52a1\u5668\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;body style=&quot;margin:0&quot;&gt;\n  &lt;canvas id=&quot;canvasElem&quot; width=&quot;100&quot; height=&quot;80&quot; style=&quot;border:1px solid&quot;&gt;&lt;\/canvas&gt;\n\n  &lt;input type=&quot;button&quot; value=&quot;Submit&quot; onclick=&quot;submit()&quot;&gt;\n\n  &lt;script&gt;\n    canvasElem.onmousemove = function(e) {\n      let ctx = canvasElem.getContext('2d');\n      ctx.lineTo(e.clientX, e.clientY);\n      ctx.stroke();\n    };\n\n    async function submit() {\n      let blob = await new Promise(resolve =&gt; canvasElem.toBlob(resolve, 'image\/png'));\n      let response = await fetch('\/article\/fetch\/post\/image', {\n        method: 'POST',\n        body: blob\n      });\n\n      \/\/ \u670d\u52a1\u5668\u7ed9\u51fa\u786e\u8ba4\u4fe1\u606f\u548c\u56fe\u7247\u5927\u5c0f\u4f5c\u4e3a\u54cd\u5e94\n      let result = await response.json();\n      alert(result.message);\n    }\n\n  &lt;\/script&gt;\n&lt;\/body&gt;\n<\/code><\/pre>\n<p>\u8bf7\u6ce8\u610f\uff0c\u8fd9\u91cc\u6211\u4eec\u6ca1\u6709\u624b\u52a8\u8bbe\u7f6e\u00a0<code>Content-Type<\/code>\u00a0header\uff0c\u56e0\u4e3a\u00a0<code>Blob<\/code>\u00a0\u5bf9\u8c61\u5177\u6709\u5185\u5efa\u7684\u7c7b\u578b\uff08\u8fd9\u91cc\u662f\u00a0<code>image\/png<\/code>\uff0c\u901a\u8fc7\u00a0<code>toBlob<\/code>\u00a0\u751f\u6210\u7684\uff09\u3002\u5bf9\u4e8e\u00a0<code>Blob<\/code>\u00a0\u5bf9\u8c61\uff0c\u8fd9\u4e2a\u7c7b\u578b\u5c31\u53d8\u6210\u4e86\u00a0<code>Content-Type<\/code>\u00a0\u7684\u503c\u3002<br \/>\n\u53ef\u4ee5\u5728\u4e0d\u4f7f\u7528\u00a0<code>async\/await<\/code>\u00a0\u7684\u60c5\u51b5\u4e0b\u91cd\u5199\u00a0<code>submit()<\/code>\u00a0\u51fd\u6570\uff0c\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">function submit() {\n  canvasElem.toBlob(function(blob) {\n    fetch('\/article\/fetch\/post\/image', {\n      method: 'POST',\n      body: blob\n    })\n      .then(response =&gt; response.json())\n      .then(result =&gt; alert(JSON.stringify(result, null, 2)))\n  }, 'image\/png');\n}\n<\/code><\/pre>\n<h1>FormData<\/h1>\n<p>\u8fd9\u4e00\u7ae0\u662f\u5173\u4e8e\u53d1\u9001 HTML \u8868\u5355\u7684\uff1a\u5e26\u6709\u6216\u4e0d\u5e26\u6587\u4ef6\uff0c\u5e26\u6709\u5176\u4ed6\u5b57\u6bb5\u7b49\u3002<br \/>\n<a href=\"https:\/\/xhr.spec.whatwg.org\/#interface-formdata\">FormData<\/a>\u00a0\u5bf9\u8c61\u53ef\u4ee5\u63d0\u4f9b\u5e2e\u52a9\u3002\u4f60\u53ef\u80fd\u5df2\u7ecf\u731c\u5230\u4e86\uff0c\u5b83\u662f\u8868\u793a HTML \u8868\u5355\u6570\u636e\u7684\u5bf9\u8c61\u3002<br \/>\n\u6784\u9020\u51fd\u6570\u662f\uff1a<\/p>\n<pre><code class=\"language-js\">let formData = new FormData([form]);\n<\/code><\/pre>\n<p>\u5982\u679c\u63d0\u4f9b\u4e86 HTML\u00a0<code>form<\/code>\u00a0\u5143\u7d20\uff0c\u5b83\u4f1a\u81ea\u52a8\u6355\u83b7\u00a0<code>form<\/code>\u00a0\u5143\u7d20\u5b57\u6bb5\u3002<br \/>\n<code>FormData<\/code>\u00a0\u7684\u7279\u6b8a\u4e4b\u5904\u5728\u4e8e\u7f51\u7edc\u65b9\u6cd5\uff08network methods\uff09\uff0c\u4f8b\u5982\u00a0<code>fetch<\/code>\u00a0\u53ef\u4ee5\u63a5\u53d7\u4e00\u4e2a\u00a0<code>FormData<\/code>\u00a0\u5bf9\u8c61\u4f5c\u4e3a body\u3002\u5b83\u4f1a\u88ab\u7f16\u7801\u5e76\u53d1\u9001\u51fa\u53bb\uff0c\u5e26\u6709\u00a0<code>Content-Type: multipart\/form-data<\/code>\u3002<br \/>\n\u4ece\u670d\u52a1\u5668\u89d2\u5ea6\u6765\u770b\uff0c\u5b83\u5c31\u50cf\u662f\u4e00\u4e2a\u666e\u901a\u7684\u8868\u5355\u63d0\u4ea4\u3002<\/p>\n<h2>\u53d1\u9001\u4e00\u4e2a\u7b80\u5355\u7684\u8868\u5355<\/h2>\n<p>\u6211\u4eec\u5148\u6765\u53d1\u9001\u4e00\u4e2a\u7b80\u5355\u7684\u8868\u5355\u3002<br \/>\n\u6b63\u5982\u4f60\u6240\u770b\u5230\u7684\uff0c\u5b83\u51e0\u4e4e\u5c31\u662f\u4e00\u884c\u4ee3\u7801\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;form id=&quot;formElem&quot;&gt;\n  &lt;input type=&quot;text&quot; name=&quot;name&quot; value=&quot;John&quot;&gt;\n  &lt;input type=&quot;text&quot; name=&quot;surname&quot; value=&quot;Smith&quot;&gt;\n  &lt;input type=&quot;submit&quot;&gt;\n&lt;\/form&gt;\n\n&lt;script&gt;\n  formElem.onsubmit = async (e) =&gt; {\n    e.preventDefault();\n\n    let response = await fetch('\/article\/formdata\/post\/user', {\n      method: 'POST',\n      body: new FormData(formElem)\n    });\n\n    let result = await response.json();\n\n    alert(result.message);\n  };\n&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u670d\u52a1\u5668\u63a5\u53d7 POST \u8bf7\u6c42\u5e76\u56de\u5e94 \u201cUser saved\u201d\u3002<\/p>\n<h2>FormData \u65b9\u6cd5<\/h2>\n<p>\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u65b9\u6cd5\u4fee\u6539\u00a0<code>FormData<\/code>\u00a0\u4e2d\u7684\u5b57\u6bb5\uff1a<\/p>\n<ul>\n<li><code>formData.append(name, value)<\/code>\u00a0\u2014\u2014 \u6dfb\u52a0\u5177\u6709\u7ed9\u5b9a\u00a0<code>name<\/code>\u00a0\u548c\u00a0<code>value<\/code>\u00a0\u7684\u8868\u5355\u5b57\u6bb5\uff0c<\/li>\n<li><code>formData.append(name, blob, fileName)<\/code>\u00a0\u2014\u2014 \u6dfb\u52a0\u4e00\u4e2a\u5b57\u6bb5\uff0c\u5c31\u50cf\u5b83\u662f\u00a0<code>&lt;input type=&quot;file&quot;&gt;<\/code>\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u00a0<code>fileName<\/code>\u00a0\u8bbe\u7f6e\u6587\u4ef6\u540d\uff08\u800c\u4e0d\u662f\u8868\u5355\u5b57\u6bb5\u540d\uff09\uff0c\u56e0\u4e3a\u5b83\u662f\u7528\u6237\u6587\u4ef6\u7cfb\u7edf\u4e2d\u6587\u4ef6\u7684\u540d\u79f0\uff0c<\/li>\n<li><code>formData.delete(name)<\/code>\u00a0\u2014\u2014 \u79fb\u9664\u5e26\u6709\u7ed9\u5b9a\u00a0<code>name<\/code>\u00a0\u7684\u5b57\u6bb5\uff0c<\/li>\n<li><code>formData.get(name)<\/code>\u00a0\u2014\u2014 \u83b7\u53d6\u5e26\u6709\u7ed9\u5b9a\u00a0<code>name<\/code>\u00a0\u7684\u5b57\u6bb5\u503c\uff0c<\/li>\n<li><code>formData.has(name)<\/code>\u00a0\u2014\u2014 \u5982\u679c\u5b58\u5728\u5e26\u6709\u7ed9\u5b9a\u00a0<code>name<\/code>\u00a0\u7684\u5b57\u6bb5\uff0c\u5219\u8fd4\u56de\u00a0<code>true<\/code>\uff0c\u5426\u5219\u8fd4\u56de\u00a0<code>false<\/code>\u3002<br \/>\n\u4ece\u6280\u672f\u4e0a\u6765\u8bb2\uff0c\u4e00\u4e2a\u8868\u5355\u53ef\u4ee5\u5305\u542b\u591a\u4e2a\u5177\u6709\u76f8\u540c\u00a0<code>name<\/code>\u00a0\u7684\u5b57\u6bb5\uff0c\u56e0\u6b64\uff0c\u591a\u6b21\u8c03\u7528\u00a0<code>append<\/code>\u00a0\u5c06\u4f1a\u6dfb\u52a0\u591a\u4e2a\u5177\u6709\u76f8\u540c\u540d\u79f0\u7684\u5b57\u6bb5\u3002<br \/>\n\u8fd8\u6709\u4e00\u4e2a\u00a0<code>set<\/code>\u00a0\u65b9\u6cd5\uff0c\u8bed\u6cd5\u4e0e\u00a0<code>append<\/code>\u00a0\u76f8\u540c\u3002\u4e0d\u540c\u4e4b\u5904\u5728\u4e8e\u00a0<code>.set<\/code>\u00a0\u79fb\u9664\u6240\u6709\u5177\u6709\u7ed9\u5b9a\u00a0<code>name<\/code>\u00a0\u7684\u5b57\u6bb5\uff0c\u7136\u540e\u9644\u52a0\u4e00\u4e2a\u65b0\u5b57\u6bb5\u3002\u56e0\u6b64\uff0c\u5b83\u786e\u4fdd\u4e86\u53ea\u6709\u4e00\u4e2a\u5177\u6709\u8fd9\u79cd\u00a0<code>name<\/code>\u00a0\u7684\u5b57\u6bb5\uff0c\u5176\u4ed6\u7684\u548c\u00a0<code>append<\/code>\u00a0\u4e00\u6837\uff1a<\/li>\n<li><code>formData.set(name, value)<\/code>\uff0c<\/li>\n<li><code>formData.set(name, blob, fileName)<\/code>\u3002<br \/>\n\u6211\u4eec\u4e5f\u53ef\u4ee5\u4f7f\u7528\u00a0<code>for..of<\/code>\u00a0\u5faa\u73af\u8fed\u4ee3 formData \u5b57\u6bb5\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let formData = new FormData();\nformData.append('key1', 'value1');\nformData.append('key2', 'value2');\n\n\/\/ \u5217\u51fa key\/value \u5bf9\nfor(let [name, value] of formData) {\n  alert(`${name} = ${value}`); \/\/ key1 = value1\uff0c\u7136\u540e\u662f key2 = value2\n}\n<\/code><\/pre>\n<h2>\u53d1\u9001\u5e26\u6709\u6587\u4ef6\u7684\u8868\u5355<\/h2>\n<p>\u8868\u5355\u59cb\u7ec8\u4ee5\u00a0<code>Content-Type: multipart\/form-data<\/code>\u00a0\u6765\u53d1\u9001\u6570\u636e\uff0c\u8fd9\u4e2a\u7f16\u7801\u5141\u8bb8\u53d1\u9001\u6587\u4ef6\u3002\u56e0\u6b64\u00a0<code>&lt;input type=&quot;file&quot;&gt;<\/code>\u00a0\u5b57\u6bb5\u4e5f\u80fd\u88ab\u53d1\u9001\uff0c\u7c7b\u4f3c\u4e8e\u666e\u901a\u7684\u8868\u5355\u63d0\u4ea4\u3002<br \/>\n\u8fd9\u662f\u5177\u6709\u8fd9\u79cd\u5f62\u5f0f\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;form id=&quot;formElem&quot;&gt;\n  &lt;input type=&quot;text&quot; name=&quot;firstName&quot; value=&quot;John&quot;&gt;\n  Picture: &lt;input type=&quot;file&quot; name=&quot;picture&quot; accept=&quot;image\/*&quot;&gt;\n  &lt;input type=&quot;submit&quot;&gt;\n&lt;\/form&gt;\n\n&lt;script&gt;\n  formElem.onsubmit = async (e) =&gt; {\n    e.preventDefault();\n\n    let response = await fetch('\/article\/formdata\/post\/user-avatar', {\n      method: 'POST',\n      body: new FormData(formElem)\n    });\n\n    let result = await response.json();\n\n    alert(result.message);\n  };\n&lt;\/script&gt;\n<\/code><\/pre>\n<h2>\u53d1\u9001\u5177\u6709 Blob \u6570\u636e\u7684\u8868\u5355<\/h2>\n<p>\u6b63\u5982\u6211\u4eec\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch\">Fetch<\/a>\u00a0\u4e00\u7ae0\u4e2d\u6240\u770b\u5230\u7684\uff0c\u4ee5\u00a0<code>Blob<\/code>\u00a0\u53d1\u9001\u4e00\u4e2a\u52a8\u6001\u751f\u6210\u7684\u4e8c\u8fdb\u5236\u6570\u636e\uff0c\u4f8b\u5982\u56fe\u7247\uff0c\u662f\u5f88\u7b80\u5355\u7684\u3002\u6211\u4eec\u53ef\u4ee5\u76f4\u63a5\u5c06\u5176\u4f5c\u4e3a\u00a0<code>fetch<\/code>\u00a0\u53c2\u6570\u7684\u00a0<code>body<\/code>\u3002<br \/>\n\u4f46\u5728\u5b9e\u9645\u4e2d\uff0c\u901a\u5e38\u66f4\u65b9\u4fbf\u7684\u53d1\u9001\u56fe\u7247\u7684\u65b9\u5f0f\u4e0d\u662f\u5355\u72ec\u53d1\u9001\uff0c\u800c\u662f\u5c06\u5176\u4f5c\u4e3a\u8868\u5355\u7684\u4e00\u90e8\u5206\uff0c\u5e76\u5e26\u6709\u9644\u52a0\u5b57\u6bb5\uff08\u4f8b\u5982 \u201cname\u201d \u548c\u5176\u4ed6 metadata\uff09\u4e00\u8d77\u53d1\u9001\u3002<br \/>\n\u5e76\u4e14\uff0c\u670d\u52a1\u5668\u901a\u5e38\u66f4\u9002\u5408\u63a5\u6536\u591a\u90e8\u5206\u7f16\u7801\u7684\u8868\u5355\uff08multipart-encoded form\uff09\uff0c\u800c\u4e0d\u662f\u539f\u59cb\u7684\u4e8c\u8fdb\u5236\u6570\u636e\u3002<br \/>\n\u4e0b\u9762\u8fd9\u4e2a\u4f8b\u5b50\u4f7f\u7528\u00a0<code>FormData<\/code>\u00a0\u5c06\u4e00\u4e2a\u6765\u81ea\u00a0<code>&lt;canvas&gt;<\/code>\u00a0\u7684\u56fe\u7247\u548c\u4e00\u4e9b\u5176\u4ed6\u5b57\u6bb5\u4e00\u8d77\u4f5c\u4e3a\u4e00\u4e2a\u8868\u5355\u63d0\u4ea4\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;body style=&quot;margin:0&quot;&gt;\n  &lt;canvas id=&quot;canvasElem&quot; width=&quot;100&quot; height=&quot;80&quot; style=&quot;border:1px solid&quot;&gt;&lt;\/canvas&gt;\n\n  &lt;input type=&quot;button&quot; value=&quot;Submit&quot; onclick=&quot;submit()&quot;&gt;\n\n  &lt;script&gt;\n    canvasElem.onmousemove = function(e) {\n      let ctx = canvasElem.getContext('2d');\n      ctx.lineTo(e.clientX, e.clientY);\n      ctx.stroke();\n    };\n\n    async function submit() {\n      let imageBlob = await new Promise(resolve =&gt; canvasElem.toBlob(resolve, 'image\/png'));\n\n      let formData = new FormData();\n      formData.append(&quot;firstName&quot;, &quot;John&quot;);\n      formData.append(&quot;image&quot;, imageBlob, &quot;image.png&quot;);\n\n      let response = await fetch('\/article\/formdata\/post\/image-form', {\n        method: 'POST',\n        body: formData\n      });\n      let result = await response.json();\n      alert(result.message);\n    }\n\n  &lt;\/script&gt;\n&lt;\/body&gt;\n<\/code><\/pre>\n<p>\u8bf7\u6ce8\u610f\u56fe\u7247\u00a0<code>Blob<\/code>\u00a0\u662f\u5982\u4f55\u6dfb\u52a0\u7684<\/p>\n<pre><code class=\"language-js\">formData.append(&quot;image&quot;, imageBlob, &quot;image.png&quot;);\n<\/code><\/pre>\n<p>\u5c31\u50cf\u8868\u5355\u4e2d\u6709\u00a0<code>&lt;input type=&quot;file&quot; name=&quot;image&quot;&gt;<\/code>\u00a0\u4e00\u6837\uff0c\u7528\u6237\u4ece\u4ed6\u4eec\u7684\u6587\u4ef6\u7cfb\u7edf\u4e2d\u4f7f\u7528\u6570\u636e\u00a0<code>imageBlob<\/code>\uff08\u7b2c\u4e8c\u4e2a\u53c2\u6570\uff09\u63d0\u4ea4\u4e86\u4e00\u4e2a\u540d\u4e3a\u00a0<code>image.png<\/code>\uff08\u7b2c\u4e09\u4e2a\u53c2\u6570\uff09\u7684\u6587\u4ef6\u3002<br \/>\n\u670d\u52a1\u5668\u8bfb\u53d6\u8868\u5355\u6570\u636e\u548c\u6587\u4ef6\uff0c\u5c31\u597d\u50cf\u5b83\u662f\u5e38\u89c4\u7684\u8868\u5355\u63d0\u4ea4\u4e00\u6837\u3002<\/p>\n<h1>Fetch \u4e0b\u8f7d\u8fdb\u5ea6<\/h1>\n<p><code>fetch<\/code>\u00a0\u65b9\u6cd5\u5141\u8bb8\u53bb\u8ddf\u8e2a\u00a0<strong>\u4e0b\u8f7d<\/strong>\u00a0\u8fdb\u5ea6\u3002<br \/>\n\u8bf7\u6ce8\u610f\uff1a\u5230\u76ee\u524d\u4e3a\u6b62\uff0c<code>fetch<\/code>\u00a0\u65b9\u6cd5\u65e0\u6cd5\u8ddf\u8e2a\u00a0<strong>\u4e0a\u4f20<\/strong>\u00a0\u8fdb\u5ea6\u3002\u5bf9\u4e8e\u8fd9\u4e2a\u76ee\u7684\uff0c\u8bf7\u4f7f\u7528\u00a0<a href=\"https:\/\/zh.javascript.info\/xmlhttprequest\">XMLHttpRequest<\/a>\uff0c\u6211\u4eec\u5728\u540e\u9762\u7ae0\u8282\u4f1a\u8bb2\u5230\u3002<br \/>\n\u8981\u8ddf\u8e2a\u4e0b\u8f7d\u8fdb\u5ea6\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>response.body<\/code>\u00a0\u5c5e\u6027\u3002\u5b83\u662f\u00a0<code>ReadableStream<\/code>\u00a0\u2014\u2014 \u4e00\u4e2a\u7279\u6b8a\u7684\u5bf9\u8c61\uff0c\u5b83\u53ef\u4ee5\u9010\u5757\uff08chunk\uff09\u63d0\u4f9b body\u3002\u5728\u00a0<a href=\"https:\/\/streams.spec.whatwg.org\/#rs-class\">Streams API<\/a>\u00a0\u89c4\u8303\u4e2d\u6709\u5bf9\u00a0<code>ReadableStream<\/code>\u00a0\u7684\u8be6\u7ec6\u63cf\u8ff0\u3002<br \/>\n\u4e0e\u00a0<code>response.text()<\/code>\uff0c<code>response.json()<\/code>\u00a0\u548c\u5176\u4ed6\u65b9\u6cd5\u4e0d\u540c\uff0c<code>response.body<\/code>\u00a0\u7ed9\u4e88\u4e86\u5bf9\u8fdb\u5ea6\u8bfb\u53d6\u7684\u5b8c\u5168\u63a7\u5236\uff0c\u6211\u4eec\u53ef\u4ee5\u968f\u65f6\u8ba1\u7b97\u4e0b\u8f7d\u4e86\u591a\u5c11\u3002<br \/>\n\u8fd9\u662f\u4ece\u00a0<code>response.body<\/code>\u00a0\u8bfb\u53d6 response \u7684\u793a\u4f8b\u4ee3\u7801\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \u4ee3\u66ff response.json() \u4ee5\u53ca\u5176\u4ed6\u65b9\u6cd5\nconst reader = response.body.getReader();\n\n\/\/ \u5728 body \u4e0b\u8f7d\u65f6\uff0c\u4e00\u76f4\u4e3a\u65e0\u9650\u5faa\u73af\nwhile(true) {\n  \/\/ \u5f53\u6700\u540e\u4e00\u5757\u4e0b\u8f7d\u5b8c\u6210\u65f6\uff0cdone \u503c\u4e3a true\n  \/\/ value \u662f\u5757\u5b57\u8282\u7684 Uint8Array\n  const {done, value} = await reader.read();\n\n  if (done) {\n    break;\n  }\n\n  console.log(`Received ${value.length} bytes`)\n}\n<\/code><\/pre>\n<p><code>await reader.read()<\/code>\u00a0\u8c03\u7528\u7684\u7ed3\u679c\u662f\u4e00\u4e2a\u5177\u6709\u4e24\u4e2a\u5c5e\u6027\u7684\u5bf9\u8c61\uff1a<\/p>\n<ul>\n<li><strong><code>done<\/code><\/strong>\u00a0\u2014\u2014 \u5f53\u8bfb\u53d6\u5b8c\u6210\u65f6\u4e3a\u00a0<code>true<\/code>\uff0c\u5426\u5219\u4e3a\u00a0<code>false<\/code>\u3002<\/li>\n<li><strong><code>value<\/code><\/strong>\u00a0\u2014\u2014 \u5b57\u8282\u7684\u7c7b\u578b\u5316\u6570\u7ec4\uff1a<code>Uint8Array<\/code>\u3002<\/li>\n<li><\/li>\n<\/ul>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\nStreams API \u8fd8\u63cf\u8ff0\u4e86\u5982\u679c\u4f7f\u7528\u00a0<code>for await..of<\/code>\u00a0\u5faa\u73af\u5f02\u6b65\u8fed\u4ee3\u00a0<code>ReadableStream<\/code>\uff0c\u4f46\u662f\u76ee\u524d\u4e3a\u6b62\uff0c\u5b83\u8fd8\u672a\u5f97\u5230\u5f88\u597d\u7684\u652f\u6301\uff08\u53c2\u89c1\u00a0<a href=\"https:\/\/github.com\/whatwg\/streams\/issues\/778#issuecomment-461341033\">\u6d4f\u89c8\u5668\u95ee\u9898<\/a>\uff09\uff0c\u6240\u4ee5\u6211\u4eec\u4f7f\u7528\u4e86\u00a0<code>while<\/code>\u00a0\u5faa\u73af\u3002<\/p>\n<\/blockquote>\n<p>\u6211\u4eec\u5728\u5faa\u73af\u4e2d\u63a5\u6536\u54cd\u5e94\u5757\uff08response chunk\uff09\uff0c\u76f4\u5230\u52a0\u8f7d\u5b8c\u6210\uff0c\u4e5f\u5c31\u662f\uff1a\u76f4\u5230\u00a0<code>done<\/code>\u00a0\u4e3a\u00a0<code>true<\/code>\u3002<br \/>\n\u8981\u5c06\u8fdb\u5ea6\u6253\u5370\u51fa\u6765\uff0c\u6211\u4eec\u53ea\u9700\u8981\u5c06\u6bcf\u4e2a\u63a5\u6536\u5230\u7684\u7247\u6bb5\u00a0<code>value<\/code>\u00a0\u7684\u957f\u5ea6\uff08length\uff09\u52a0\u5230 counter \u5373\u53ef\u3002<br \/>\n\u8fd9\u662f\u83b7\u53d6\u54cd\u5e94\uff0c\u5e76\u5728\u63a7\u5236\u53f0\u4e2d\u8bb0\u5f55\u8fdb\u5ea6\u7684\u5b8c\u6574\u5de5\u4f5c\u793a\u4f8b\uff0c\u4e0b\u9762\u6709\u66f4\u591a\u8bf4\u660e\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ Step 1\uff1a\u542f\u52a8 fetch\uff0c\u5e76\u83b7\u5f97\u4e00\u4e2a reader\nlet response = await fetch('https:\/\/api.github.com\/repos\/javascript-tutorial\/en.javascript.info\/commits?per_page=100');\n\nconst reader = response.body.getReader();\n\n\/\/ Step 2\uff1a\u83b7\u5f97\u603b\u957f\u5ea6\uff08length\uff09\nconst contentLength = +response.headers.get('Content-Length');\n\n\/\/ Step 3\uff1a\u8bfb\u53d6\u6570\u636e\nlet receivedLength = 0; \/\/ \u5f53\u524d\u63a5\u6536\u5230\u4e86\u8fd9\u4e48\u591a\u5b57\u8282\nlet chunks = []; \/\/ \u63a5\u6536\u5230\u7684\u4e8c\u8fdb\u5236\u5757\u7684\u6570\u7ec4\uff08\u5305\u62ec body\uff09\nwhile(true) {\n  const {done, value} = await reader.read();\n\n  if (done) {\n    break;\n  }\n\n  chunks.push(value);\n  receivedLength += value.length;\n\n  console.log(`Received ${receivedLength} of ${contentLength}`)\n}\n\n\/\/ Step 4\uff1a\u5c06\u5757\u8fde\u63a5\u5230\u5355\u4e2a Uint8Array\nlet chunksAll = new Uint8Array(receivedLength); \/\/ (4.1)\nlet position = 0;\nfor(let chunk of chunks) {\n  chunksAll.set(chunk, position); \/\/ (4.2)\n  position += chunk.length;\n}\n\n\/\/ Step 5\uff1a\u89e3\u7801\u6210\u5b57\u7b26\u4e32\nlet result = new TextDecoder(&quot;utf-8&quot;).decode(chunksAll);\n\n\/\/ \u6211\u4eec\u5b8c\u6210\u5566\uff01\nlet commits = JSON.parse(result);\nalert(commits[0].author.login);\n<\/code><\/pre>\n<p>\u8ba9\u6211\u4eec\u4e00\u6b65\u6b65\u89e3\u91ca\u4e0b\u8fd9\u4e2a\u8fc7\u7a0b\uff1a<\/p>\n<ol>\n<li>\u6211\u4eec\u50cf\u5f80\u5e38\u4e00\u6837\u6267\u884c\u00a0<code>fetch<\/code>\uff0c\u4f46\u4e0d\u662f\u8c03\u7528\u00a0<code>response.json()<\/code>\uff0c\u800c\u662f\u83b7\u5f97\u4e86\u4e00\u4e2a\u6d41\u8bfb\u53d6\u5668\uff08stream reader\uff09<code>response.body.getReader()<\/code>\u3002<br \/>\n\u8bf7\u6ce8\u610f\uff0c\u6211\u4eec\u4e0d\u80fd\u540c\u65f6\u4f7f\u7528\u8fd9\u4e24\u79cd\u65b9\u6cd5\u6765\u8bfb\u53d6\u76f8\u540c\u7684\u54cd\u5e94\u3002\u8981\u4e48\u4f7f\u7528\u6d41\u8bfb\u53d6\u5668\uff0c\u8981\u4e48\u4f7f\u7528 reponse \u65b9\u6cd5\u6765\u83b7\u53d6\u7ed3\u679c\u3002<\/li>\n<li>\u5728\u8bfb\u53d6\u6570\u636e\u4e4b\u524d\uff0c\u6211\u4eec\u53ef\u4ee5\u4ece\u00a0<code>Content-Length<\/code>\u00a0header \u4e2d\u5f97\u5230\u5b8c\u6574\u7684\u54cd\u5e94\u957f\u5ea6\u3002<br \/>\n\u8de8\u6e90\u8bf7\u6c42\u4e2d\u53ef\u80fd\u4e0d\u5b58\u5728\u8fd9\u4e2a header\uff08\u8bf7\u53c2\u89c1\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">Fetch\uff1a\u8de8\u6e90\u8bf7\u6c42<\/a>\uff09\uff0c\u5e76\u4e14\u4ece\u6280\u672f\u4e0a\u8bb2\uff0c\u670d\u52a1\u5668\u53ef\u4ee5\u4e0d\u8bbe\u7f6e\u5b83\u3002\u4f46\u662f\u901a\u5e38\u60c5\u51b5\u4e0b\u5b83\u90fd\u4f1a\u5728\u90a3\u91cc\u3002<\/li>\n<li>\u8c03\u7528\u00a0<code>await reader.read()<\/code>\uff0c\u76f4\u5230\u5b83\u5b8c\u6210\u3002<br \/>\n\u6211\u4eec\u5c06\u54cd\u5e94\u5757\u6536\u96c6\u5230\u6570\u7ec4\u00a0<code>chunks<\/code>\u00a0\u4e2d\u3002\u8fd9\u5f88\u91cd\u8981\uff0c\u56e0\u4e3a\u5728\u4f7f\u7528\u5b8c\uff08consumed\uff09\u54cd\u5e94\u540e\uff0c\u6211\u4eec\u5c06\u65e0\u6cd5\u4f7f\u7528\u00a0<code>response.json()<\/code>\u00a0\u6216\u8005\u5176\u4ed6\u65b9\u5f0f\uff08\u4f60\u53ef\u4ee5\u8bd5\u8bd5\uff0c\u5c06\u4f1a\u51fa\u73b0 error\uff09\u53bb\u201c\u91cd\u65b0\u8bfb\u53d6\u201d\u5b83\u3002<\/li>\n<li>\u6700\u540e\uff0c\u6211\u4eec\u6709\u4e86\u4e00\u4e2a\u00a0<code>chunks<\/code>\u00a0\u2014\u2014 \u4e00\u4e2a\u00a0<code>Uint8Array<\/code>\u00a0\u5b57\u8282\u5757\u6570\u7ec4\u3002\u6211\u4eec\u9700\u8981\u5c06\u8fd9\u4e9b\u5757\u5408\u5e76\u6210\u4e00\u4e2a\u7ed3\u679c\u3002\u4f46\u4e0d\u5e78\u7684\u662f\uff0c\u6ca1\u6709\u5355\u4e2a\u65b9\u6cd5\u53ef\u4ee5\u5c06\u5b83\u4eec\u4e32\u8054\u8d77\u6765\uff0c\u6240\u4ee5\u8fd9\u91cc\u9700\u8981\u4e00\u4e9b\u4ee3\u7801\u6765\u5b9e\u73b0\uff1a\n<ol>\n<li>\u6211\u4eec\u521b\u5efa\u00a0<code>chunksAll = new Uint8Array(receivedLength)<\/code>\u00a0\u2014\u2014 \u4e00\u4e2a\u5177\u6709\u6240\u6709\u6570\u636e\u5757\u5408\u5e76\u540e\u7684\u957f\u5ea6\u7684\u540c\u7c7b\u578b\u6570\u7ec4\u3002<\/li>\n<li>\u7136\u540e\u4f7f\u7528\u00a0<code>.set(chunk, position)<\/code>\u00a0\u65b9\u6cd5\uff0c\u4ece\u6570\u7ec4\u4e2d\u4e00\u4e2a\u4e2a\u5730\u590d\u5236\u8fd9\u4e9b\u00a0<code>chunk<\/code>\u3002<\/li>\n<\/ol>\n<\/li>\n<li>\u6211\u4eec\u7684\u7ed3\u679c\u73b0\u5728\u50a8\u5b58\u5728\u00a0<code>chunksAll<\/code>\u00a0\u4e2d\u3002\u4f46\u5b83\u662f\u4e00\u4e2a\u5b57\u8282\u6570\u7ec4\uff0c\u4e0d\u662f\u5b57\u7b26\u4e32\u3002<br \/>\n\u8981\u521b\u5efa\u4e00\u4e2a\u5b57\u7b26\u4e32\uff0c\u6211\u4eec\u9700\u8981\u89e3\u6790\u8fd9\u4e9b\u5b57\u8282\u3002\u53ef\u4ee5\u4f7f\u7528\u5185\u5efa\u7684\u00a0<a href=\"https:\/\/zh.javascript.info\/text-decoder\">TextDecoder<\/a>\u00a0\u5bf9\u8c61\u5b8c\u6210\u3002\u7136\u540e\uff0c\u6211\u4eec\u53ef\u4ee5\u00a0<code>JSON.parse<\/code>\u00a0\u5b83\uff0c\u5982\u679c\u6709\u5fc5\u8981\u7684\u8bdd\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u9700\u8981\u7684\u662f\u4e8c\u8fdb\u5236\u5185\u5bb9\u800c\u4e0d\u662f\u5b57\u7b26\u4e32\u5462\uff1f\u8fd9\u66f4\u7b80\u5355\u3002\u7528\u4e0b\u9762\u8fd9\u884c\u4ee3\u7801\u66ff\u6362\u6389\u7b2c 4 \u548c\u7b2c 5 \u6b65\uff0c\u8fd9\u884c\u4ee3\u7801\u4ece\u6240\u6709\u5757\u521b\u5efa\u4e00\u4e2a\u00a0<code>Blob<\/code>\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">let blob = new Blob(chunks);\n<\/code><\/pre>\n<p>\u6700\u540e\uff0c\u6211\u4eec\u5f97\u5230\u4e86\u7ed3\u679c\uff08\u4ee5\u5b57\u7b26\u4e32\u6216 blob \u7684\u5f62\u5f0f\u8868\u793a\uff0c\u4ec0\u4e48\u65b9\u4fbf\u5c31\u7528\u4ec0\u4e48\uff09\uff0c\u5e76\u5728\u8fc7\u7a0b\u4e2d\u5bf9\u8fdb\u5ea6\u8fdb\u884c\u4e86\u8ddf\u8e2a\u3002<br \/>\n\u518d\u5f3a\u8c03\u4e00\u904d\uff0c\u8fd9\u4e0d\u80fd\u7528\u4e8e\u00a0<strong>\u4e0a\u4f20<\/strong>\u00a0\u8fc7\u7a0b\uff08\u73b0\u5728\u65e0\u6cd5\u901a\u8fc7\u00a0<code>fetch<\/code>\u00a0\u83b7\u53d6\uff09\uff0c\u4ec5\u7528\u4e8e\u00a0<strong>\u4e0b\u8f7d<\/strong>\u00a0\u8fc7\u7a0b\u3002<br \/>\n\u53e6\u5916\uff0c\u5982\u679c\u5927\u5c0f\u672a\u77e5\uff0c\u6211\u4eec\u5e94\u8be5\u68c0\u67e5\u5faa\u73af\u4e2d\u7684\u00a0<code>receivedLength<\/code>\uff0c\u4e00\u65e6\u8fbe\u5230\u4e00\u5b9a\u7684\u9650\u5236\u5c31\u5c06\u5176\u4e2d\u65ad\u3002\u8fd9\u6837\u00a0<code>chunks<\/code>\u00a0\u5c31\u4e0d\u4f1a\u6ea2\u51fa\u5185\u5b58\u4e86\u3002<\/p>\n<h1>Fetch: \u4e2d\u6b62\uff08Abort\uff09<\/h1>\n<p>\u6b63\u5982\u6211\u4eec\u6240\u77e5\u9053\u7684\uff0c<code>fetch<\/code>\u00a0\u8fd4\u56de\u4e00\u4e2a promise\u3002JavaScript \u901a\u5e38\u5e76\u6ca1\u6709\u201c\u4e2d\u6b62\u201d promise \u7684\u6982\u5ff5\u3002\u90a3\u4e48\u6211\u4eec\u600e\u6837\u624d\u80fd\u53d6\u6d88\u4e00\u4e2a\u6b63\u5728\u6267\u884c\u7684\u00a0<code>fetch<\/code>\u00a0\u5462\uff1f\u4f8b\u5982\uff0c\u5982\u679c\u7528\u6237\u5728\u6211\u4eec\u7f51\u7ad9\u4e0a\u7684\u64cd\u4f5c\u8868\u660e\u4e0d\u518d\u9700\u8981\u67d0\u4e2a\u6267\u884c\u4e2d\u7684\u00a0<code>fetch<\/code>\u3002<br \/>\n\u4e3a\u6b64\u6709\u4e00\u4e2a\u7279\u6b8a\u7684\u5185\u5efa\u5bf9\u8c61\uff1a<code>AbortController<\/code>\u3002\u5b83\u4e0d\u4ec5\u53ef\u4ee5\u4e2d\u6b62\u00a0<code>fetch<\/code>\uff0c\u8fd8\u53ef\u4ee5\u4e2d\u6b62\u5176\u4ed6\u5f02\u6b65\u4efb\u52a1\u3002<br \/>\n\u7528\u6cd5\u975e\u5e38\u7b80\u5355\u3002<\/p>\n<h2>AbortController \u5bf9\u8c61<\/h2>\n<p>\u521b\u5efa\u4e00\u4e2a\u63a7\u5236\u5668\uff08controller\uff09\uff1a<\/p>\n<pre><code class=\"language-js\">let controller = new AbortController();\n<\/code><\/pre>\n<p>\u63a7\u5236\u5668\u662f\u4e00\u4e2a\u6781\u5176\u7b80\u5355\u7684\u5bf9\u8c61\u3002<\/p>\n<ul>\n<li>\u5b83\u5177\u6709\u5355\u4e2a\u65b9\u6cd5\u00a0<code>abort()<\/code>\uff0c<\/li>\n<li>\u548c\u5355\u4e2a\u5c5e\u6027\u00a0<code>signal<\/code>\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u8fd9\u4e2a\u5c5e\u6027\u4e0a\u8bbe\u7f6e\u4e8b\u4ef6\u76d1\u542c\u5668\u3002<br \/>\n\u5f53\u00a0<code>abort()<\/code>\u00a0\u88ab\u8c03\u7528\u65f6\uff1a<\/li>\n<li><code>controller.signal<\/code>\u00a0\u5c31\u4f1a\u89e6\u53d1\u00a0<code>abort<\/code>\u00a0\u4e8b\u4ef6\u3002<\/li>\n<li><code>controller.signal.aborted<\/code>\u00a0\u5c5e\u6027\u53d8\u4e3a\u00a0<code>true<\/code>\u3002<br \/>\n\u901a\u5e38\uff0c\u6211\u4eec\u9700\u8981\u5904\u7406\u4e24\u90e8\u5206\uff1a<\/li>\n<\/ul>\n<ol>\n<li>\u4e00\u90e8\u5206\u662f\u901a\u8fc7\u5728\u00a0<code>controller.signal<\/code>\u00a0\u4e0a\u6dfb\u52a0\u4e00\u4e2a\u76d1\u542c\u5668\uff0c\u6765\u6267\u884c\u53ef\u53d6\u6d88\u64cd\u4f5c\u3002<\/li>\n<li>\u53e6\u4e00\u90e8\u5206\u662f\u89e6\u53d1\u53d6\u6d88\uff1a\u5728\u9700\u8981\u7684\u65f6\u5019\u8c03\u7528\u00a0<code>controller.abort()<\/code>\u3002<br \/>\n\u8fd9\u662f\u5b8c\u6574\u7684\u793a\u4f8b\uff08\u76ee\u524d\u8fd8\u6ca1\u6709\u00a0<code>fetch<\/code>\uff09\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">let controller = new AbortController();\nlet signal = controller.signal;\n\n\/\/ \u6267\u884c\u53ef\u53d6\u6d88\u64cd\u4f5c\u90e8\u5206\n\/\/ \u83b7\u53d6 &quot;signal&quot; \u5bf9\u8c61\uff0c\n\/\/ \u5e76\u5c06\u76d1\u542c\u5668\u8bbe\u7f6e\u4e3a\u5728 controller.abort() \u88ab\u8c03\u7528\u65f6\u89e6\u53d1\nsignal.addEventListener('abort', () =&gt; alert(&quot;abort!&quot;));\n\n\/\/ \u53e6\u4e00\u90e8\u5206\uff0c\u53d6\u6d88\uff08\u5728\u4e4b\u540e\u7684\u4efb\u4f55\u65f6\u5019\uff09\uff1a\ncontroller.abort(); \/\/ \u4e2d\u6b62\uff01\n\n\/\/ \u4e8b\u4ef6\u89e6\u53d1\uff0csignal.aborted \u53d8\u4e3a true\nalert(signal.aborted); \/\/ true\n<\/code><\/pre>\n<p>\u6b63\u5982\u6211\u4eec\u6240\u770b\u5230\u7684\uff0c<code>AbortController<\/code>\u00a0\u53ea\u662f\u5728\u00a0<code>abort()<\/code>\u00a0\u88ab\u8c03\u7528\u65f6\u4f20\u9012\u00a0<code>abort<\/code>\u00a0\u4e8b\u4ef6\u7684\u4e00\u79cd\u65b9\u5f0f\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u81ea\u5df1\u5728\u4ee3\u7801\u4e2d\u5b9e\u73b0\u76f8\u540c\u7c7b\u578b\u7684\u4e8b\u4ef6\u76d1\u542c\uff0c\u800c\u4e0d\u9700\u8981\u00a0<code>AbortController<\/code>\u00a0\u5bf9\u8c61\u3002<br \/>\n\u4f46\u662f\u6709\u4ef7\u503c\u7684\u662f\uff0c<code>fetch<\/code>\u00a0\u77e5\u9053\u5982\u4f55\u4e0e\u00a0<code>AbortController<\/code>\u00a0\u5bf9\u8c61\u4e00\u8d77\u5de5\u4f5c\u3002\u5b83\u4eec\u662f\u96c6\u6210\u5728\u4e00\u8d77\u7684\u3002<\/p>\n<h2>\u4e0e fetch \u4e00\u8d77\u4f7f\u7528<\/h2>\n<p>\u4e3a\u4e86\u80fd\u591f\u53d6\u6d88\u00a0<code>fetch<\/code>\uff0c\u8bf7\u5c06\u00a0<code>AbortController<\/code>\u00a0\u7684\u00a0<code>signal<\/code>\u00a0\u5c5e\u6027\u4f5c\u4e3a\u00a0<code>fetch<\/code>\u00a0\u7684\u4e00\u4e2a\u53ef\u9009\u53c2\u6570\uff08option\uff09\u8fdb\u884c\u4f20\u9012\uff1a<\/p>\n<pre><code class=\"language-js\">let controller = new AbortController();\nfetch(url, {\n  signal: controller.signal\n});\n<\/code><\/pre>\n<p><code>fetch<\/code>\u00a0\u65b9\u6cd5\u77e5\u9053\u5982\u4f55\u4e0e\u00a0<code>AbortController<\/code>\u00a0\u4e00\u8d77\u5de5\u4f5c\u3002\u5b83\u4f1a\u76d1\u542c\u00a0<code>signal<\/code>\u00a0\u4e0a\u7684\u00a0<code>abort<\/code>\u00a0\u4e8b\u4ef6\u3002<br \/>\n\u73b0\u5728\uff0c\u60f3\u8981\u4e2d\u6b62\u00a0<code>fetch<\/code>\uff0c\u8c03\u7528\u00a0<code>controller.abort()<\/code>\u00a0\u5373\u53ef\uff1a<\/p>\n<pre><code class=\"language-js\">controller.abort();\n<\/code><\/pre>\n<p>\u6211\u4eec\u5b8c\u6210\u5566\uff1a<code>fetch<\/code>\u00a0\u4ece\u00a0<code>signal<\/code>\u00a0\u83b7\u53d6\u4e86\u4e8b\u4ef6\u5e76\u4e2d\u6b62\u4e86\u8bf7\u6c42\u3002<br \/>\n\u5f53\u4e00\u4e2a fetch \u88ab\u4e2d\u6b62\uff0c\u5b83\u7684 promise \u5c31\u4f1a\u4ee5\u4e00\u4e2a error\u00a0<code>AbortError<\/code>\u00a0reject\uff0c\u56e0\u6b64\u6211\u4eec\u5e94\u8be5\u5bf9\u5176\u8fdb\u884c\u5904\u7406\uff0c\u4f8b\u5982\u5728\u00a0<code>try..catch<\/code>\u00a0\u4e2d\u3002<br \/>\n\u8fd9\u662f\u5b8c\u6574\u7684\u793a\u4f8b\uff0c\u5176\u4e2d\u00a0<code>fetch<\/code>\u00a0\u5728 1 \u79d2\u540e\u4e2d\u6b62\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ 1 \u79d2\u540e\u4e2d\u6b62\nlet controller = new AbortController();\nsetTimeout(() =&gt; controller.abort(), 1000);\n\ntry {\n  let response = await fetch('\/article\/fetch-abort\/demo\/hang', {\n    signal: controller.signal\n  });\n} catch(err) {\n  if (err.name == 'AbortError') { \/\/ handle abort()\n    alert(&quot;Aborted!&quot;);\n  } else {\n    throw err;\n  }\n}\n<\/code><\/pre>\n<h2>AbortController \u662f\u53ef\u4f38\u7f29\u7684<\/h2>\n<p><code>AbortController<\/code>\u00a0\u662f\u53ef\u4f38\u7f29\u7684\u3002\u5b83\u5141\u8bb8\u4e00\u6b21\u53d6\u6d88\u591a\u4e2a fetch\u3002<br \/>\n\u8fd9\u662f\u4e00\u4e2a\u4ee3\u7801\u8349\u7a3f\uff0c\u8be5\u4ee3\u7801\u5e76\u884c fetch \u5f88\u591a\u00a0<code>urls<\/code>\uff0c\u5e76\u4f7f\u7528\u5355\u4e2a\u63a7\u5236\u5668\u5c06\u5176\u5168\u90e8\u4e2d\u6b62\uff1a<\/p>\n<pre><code class=\"language-js\">let urls = [...]; \/\/ \u8981\u5e76\u884c fetch \u7684 url \u5217\u8868\n\nlet controller = new AbortController();\n\n\/\/ \u4e00\u4e2a fetch promise \u7684\u6570\u7ec4\nlet fetchJobs = urls.map(url =&gt; fetch(url, {\n  signal: controller.signal\n}));\n\nlet results = await Promise.all(fetchJobs);\n\n\/\/ controller.abort() \u88ab\u4ece\u4efb\u4f55\u5730\u65b9\u8c03\u7528\uff0c\n\/\/ \u5b83\u90fd\u5c06\u4e2d\u6b62\u6240\u6709 fetch\n<\/code><\/pre>\n<p>\u5982\u679c\u6211\u4eec\u6709\u81ea\u5df1\u7684\u4e0e\u00a0<code>fetch<\/code>\u00a0\u4e0d\u540c\u7684\u5f02\u6b65\u4efb\u52a1\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5355\u4e2a\u00a0<code>AbortController<\/code>\u00a0\u4e2d\u6b62\u8fd9\u4e9b\u4efb\u52a1\u4ee5\u53ca fetch\u3002<br \/>\n\u5728\u6211\u4eec\u7684\u4efb\u52a1\u4e2d\uff0c\u6211\u4eec\u53ea\u9700\u8981\u76d1\u542c\u5176\u00a0<code>abort<\/code>\u00a0\u4e8b\u4ef6\uff1a<\/p>\n<pre><code class=\"language-js\">let urls = [...];\nlet controller = new AbortController();\n\nlet ourJob = new Promise((resolve, reject) =&gt; { \/\/ \u6211\u4eec\u7684\u4efb\u52a1\n  ...\n  controller.signal.addEventListener('abort', reject);\n});\n\nlet fetchJobs = urls.map(url =&gt; fetch(url, { \/\/ fetches\n  signal: controller.signal\n}));\n\n\/\/ \u7b49\u5f85\u5b8c\u6210\u6211\u4eec\u7684\u4efb\u52a1\u548c\u6240\u6709 fetch\nlet results = await Promise.all([...fetchJobs, ourJob]);\n\n\/\/ controller.abort() \u88ab\u4ece\u4efb\u4f55\u5730\u65b9\u8c03\u7528\uff0c\n\/\/ \u5b83\u90fd\u5c06\u4e2d\u6b62\u6240\u6709 fetch \u548c ourJob\n<\/code><\/pre>\n<h1>Fetch: \u8de8\u6e90\u8bf7\u6c42<\/h1>\n<p>\u5982\u679c\u6211\u4eec\u5411\u53e6\u4e00\u4e2a\u7f51\u7ad9\u53d1\u9001\u00a0<code>fetch<\/code>\u00a0\u8bf7\u6c42\uff0c\u5219\u8be5\u8bf7\u6c42\u53ef\u80fd\u4f1a\u5931\u8d25\u3002<br \/>\n\u4f8b\u5982\uff0c\u8ba9\u6211\u4eec\u5c1d\u8bd5\u5411\u00a0<code>http:\/\/example.com<\/code>\u00a0\u53d1\u9001\u00a0<code>fetch<\/code>\u00a0\u8bf7\u6c42\uff1a<\/p>\n<pre><code class=\"language-js\">try {\n  await fetch('http:\/\/example.com');\n} catch(err) {\n  alert(err); \/\/ fetch \u5931\u8d25\n}\n<\/code><\/pre>\n<p>\u6b63\u5982\u6240\u6599\uff0c\u83b7\u53d6\u5931\u8d25\u3002<br \/>\n\u8fd9\u91cc\u7684\u6838\u5fc3\u6982\u5ff5\u662f\u00a0<strong>\u6e90\uff08origin\uff09<\/strong>\u2014\u2014 \u57df\uff08domain\uff09\/\u7aef\u53e3\uff08port\uff09\/\u534f\u8bae\uff08protocol\uff09\u7684\u7ec4\u5408\u3002<br \/>\n\u8de8\u6e90\u8bf7\u6c42 \u2014\u2014 \u90a3\u4e9b\u53d1\u9001\u5230\u5176\u4ed6\u57df\uff08\u5373\u4f7f\u662f\u5b50\u57df\uff09\u3001\u534f\u8bae\u6216\u7aef\u53e3\u7684\u8bf7\u6c42 \u2014\u2014 \u9700\u8981\u6765\u81ea\u8fdc\u7a0b\u7aef\u7684\u7279\u6b8a header\u3002<br \/>\n\u8fd9\u4e2a\u7b56\u7565\u88ab\u79f0\u4e3a \u201cCORS\u201d\uff1a\u8de8\u6e90\u8d44\u6e90\u5171\u4eab\uff08Cross-Origin Resource Sharing\uff09\u3002<\/p>\n<h2>\u4e3a\u4ec0\u4e48\u9700\u8981 CORS? \u8de8\u6e90\u8bf7\u6c42\u7b80\u53f2<\/h2>\n<p>CORS \u7684\u5b58\u5728\u662f\u4e3a\u4e86\u4fdd\u62a4\u4e92\u8054\u7f51\u514d\u53d7\u9ed1\u5ba2\u653b\u51fb\u3002<br \/>\n\u8bf4\u771f\u7684\uff0c\u5728\u8fd9\u8bf4\u70b9\u513f\u9898\u5916\u8bdd\uff0c\u8bb2\u8bb2\u5b83\u7684\u5386\u53f2\u3002<br \/>\n<strong>\u591a\u5e74\u6765\uff0c\u6765\u81ea\u4e00\u4e2a\u7f51\u7ad9\u7684\u811a\u672c\u65e0\u6cd5\u8bbf\u95ee\u53e6\u4e00\u4e2a\u7f51\u7ad9\u7684\u5185\u5bb9\u3002<\/strong><br \/>\n\u8fd9\u4e2a\u7b80\u5355\u6709\u529b\u7684\u89c4\u5219\u662f\u4e92\u8054\u7f51\u5b89\u5168\u7684\u57fa\u7840\u3002\u4f8b\u5982\uff0c\u6765\u81ea\u00a0<code>hacker.com<\/code>\u00a0\u7684\u811a\u672c\u65e0\u6cd5\u8bbf\u95ee\u00a0<code>gmail.com<\/code>\u00a0\u4e0a\u7684\u7528\u6237\u90ae\u7bb1\u3002\u57fa\u4e8e\u8fd9\u6837\u7684\u89c4\u5219\uff0c\u4eba\u4eec\u611f\u5230\u5f88\u5b89\u5168\u3002<br \/>\n\u5728\u90a3\u65f6\u5019\uff0cJavaScript \u5e76\u6ca1\u6709\u4efb\u4f55\u7279\u6b8a\u7684\u6267\u884c\u7f51\u7edc\u8bf7\u6c42\u7684\u65b9\u6cd5\u3002\u5b83\u53ea\u662f\u4e00\u79cd\u7528\u6765\u88c5\u9970\u7f51\u9875\u7684\u73a9\u5177\u8bed\u8a00\u800c\u5df2\u3002<br \/>\n\u4f46\u662f Web \u5f00\u53d1\u4eba\u5458\u9700\u8981\u66f4\u591a\u529f\u80fd\u3002\u4eba\u4eec\u53d1\u660e\u4e86\u5404\u79cd\u5404\u6837\u7684\u6280\u5de7\u53bb\u7a81\u7834\u8be5\u9650\u5236\uff0c\u5e76\u5411\u5176\u4ed6\u7f51\u7ad9\u53d1\u51fa\u8bf7\u6c42\u3002<\/p>\n<h3>\u4f7f\u7528\u8868\u5355<\/h3>\n<p>\u5176\u4e2d\u4e00\u79cd\u548c\u5176\u4ed6\u670d\u52a1\u5668\u901a\u4fe1\u7684\u65b9\u6cd5\u662f\u5728\u90a3\u91cc\u63d0\u4ea4\u4e00\u4e2a\u00a0<code>&lt;form&gt;<\/code>\u3002\u4eba\u4eec\u5c06\u5b83\u63d0\u4ea4\u5230\u00a0<code>&lt;iframe&gt;<\/code>\uff0c\u53ea\u662f\u4e3a\u4e86\u505c\u7559\u5728\u5f53\u524d\u9875\u9762\uff0c\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">&lt;!-- \u8868\u5355\u76ee\u6807 --&gt;\n&lt;iframe name=&quot;iframe&quot;&gt;&lt;\/iframe&gt;\n\n&lt;!-- \u8868\u5355\u53ef\u4ee5\u7531 JavaScript \u52a8\u6001\u751f\u6210\u5e76\u63d0\u4ea4 --&gt;\n&lt;form target=&quot;iframe&quot; method=&quot;POST&quot; action=&quot;http:\/\/another.com\/\u2026&quot;&gt;\n  ...\n&lt;\/form&gt;\n<\/code><\/pre>\n<p>\u56e0\u6b64\uff0c\u5373\u4f7f\u6ca1\u6709\u7f51\u7edc\u65b9\u6cd5\uff0c\u4e5f\u53ef\u4ee5\u5411\u5176\u4ed6\u7f51\u7ad9\u53d1\u51fa GET\/POST \u8bf7\u6c42\uff0c\u56e0\u4e3a\u8868\u5355\u53ef\u4ee5\u5c06\u6570\u636e\u53d1\u9001\u5230\u4efb\u4f55\u5730\u65b9\u3002\u4f46\u662f\u7531\u4e8e\u7981\u6b62\u4ece\u5176\u4ed6\u7f51\u7ad9\u8bbf\u95ee\u00a0<code>&lt;iframe&gt;<\/code>\u00a0\u4e2d\u7684\u5185\u5bb9\uff0c\u56e0\u6b64\u5c31\u65e0\u6cd5\u8bfb\u53d6\u54cd\u5e94\u3002<br \/>\n\u786e\u5207\u5730\u8bf4\uff0c\u5b9e\u9645\u4e0a\u6709\u4e00\u4e9b\u6280\u5de7\u80fd\u591f\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u8fd9\u5728 iframe \u548c\u9875\u9762\u4e2d\u90fd\u9700\u8981\u6dfb\u52a0\u7279\u6b8a\u811a\u672c\u3002\u56e0\u6b64\uff0c\u4e0e iframe \u7684\u901a\u4fe1\u5728\u6280\u672f\u4e0a\u662f\u53ef\u80fd\u7684\u3002\u73b0\u5728\u6211\u4eec\u6ca1\u5fc5\u8981\u8bb2\u5176\u7ec6\u8282\u5185\u5bb9\uff0c\u6211\u4eec\u8fd8\u662f\u8ba9\u8fd9\u4e9b\u53e4\u8463\u4ee3\u7801\u4e0d\u8981\u518d\u51fa\u73b0\u4e86\u5427\u3002<\/p>\n<h3>\u4f7f\u7528 script<\/h3>\n<p>\u53e6\u4e00\u4e2a\u6280\u5de7\u662f\u4f7f\u7528\u00a0<code>script<\/code>\u00a0\u6807\u7b7e\u3002<code>script<\/code>\u00a0\u53ef\u4ee5\u5177\u6709\u4efb\u4f55\u57df\u7684\u00a0<code>src<\/code>\uff0c\u4f8b\u5982\u00a0<code>&lt;script src=&quot;http:\/\/another.com\/\u2026&quot;&gt;<\/code>\u3002\u4e5f\u53ef\u4ee5\u6267\u884c\u6765\u81ea\u4efb\u4f55\u7f51\u7ad9\u7684\u00a0<code>script<\/code>\u3002<br \/>\n\u5982\u679c\u4e00\u4e2a\u7f51\u7ad9\uff0c\u4f8b\u5982\u00a0<code>another.com<\/code>\u00a0\u8bd5\u56fe\u516c\u5f00\u8fd9\u79cd\u8bbf\u95ee\u65b9\u5f0f\u7684\u6570\u636e\uff0c\u5219\u4f1a\u4f7f\u7528\u6240\u8c13\u7684 \u201cJSONP (JSON with padding)\u201d \u534f\u8bae\u3002<br \/>\n\u8fd9\u662f\u5b83\u7684\u5de5\u4f5c\u65b9\u5f0f\u3002<br \/>\n\u5047\u8bbe\u5728\u6211\u4eec\u7684\u7f51\u7ad9\uff0c\u9700\u8981\u4ee5\u8fd9\u79cd\u65b9\u5f0f\u4ece\u00a0<code>http:\/\/another.com<\/code>\u00a0\u7f51\u7ad9\u83b7\u53d6\u6570\u636e\uff0c\u4f8b\u5982\u5929\u6c14\uff1a<\/p>\n<ol>\n<li>\u9996\u5148\uff0c\u6211\u4eec\u5148\u58f0\u660e\u4e00\u4e2a\u5168\u5c40\u51fd\u6570\u6765\u63a5\u6536\u6570\u636e\uff0c\u4f8b\u5982\u00a0<code>gotWeather<\/code>\u3002<\/li>\n<\/ol>\n<pre><code class=\"language-js\">\/\/ 1. \u58f0\u660e\u5904\u7406\u5929\u6c14\u6570\u636e\u7684\u51fd\u6570\nfunction gotWeather({ temperature, humidity }) {\n  alert(`temperature: ${temperature}, humidity: ${humidity}`);\n}\n<\/code><\/pre>\n<ol start=\"2\">\n<li>\u7136\u540e\u6211\u4eec\u521b\u5efa\u4e00\u4e2a\u7279\u6027\uff08attribute\uff09\u4e3a\u00a0<code>src=&quot;http:\/\/another.com\/weather.json?callback=gotWeather&quot;<\/code>\u00a0\u7684\u00a0<code>&lt;script&gt;<\/code>\u00a0\u6807\u7b7e\uff0c\u4f7f\u7528\u6211\u4eec\u7684\u51fd\u6570\u540d\u4f5c\u4e3a\u5b83\u7684\u00a0<code>callback<\/code>\u00a0URL-\u53c2\u6570\u3002<\/li>\n<\/ol>\n<pre><code class=\"language-js\">let script = document.createElement('script');\nscript.src = `http:\/\/another.com\/weather.json?callback=gotWeather`;\ndocument.body.append(script);\n<\/code><\/pre>\n<ol start=\"3\">\n<li>\u8fdc\u7a0b\u670d\u52a1\u5668\u00a0<code>another.com<\/code>\u00a0\u52a8\u6001\u751f\u6210\u4e00\u4e2a\u811a\u672c\uff0c\u8be5\u811a\u672c\u8c03\u7528\u00a0<code>gotWeather(...)<\/code>\uff0c\u53d1\u9001\u5b83\u60f3\u8ba9\u6211\u4eec\u63a5\u6536\u7684\u6570\u636e\u3002<\/li>\n<\/ol>\n<pre><code class=\"language-js\">\/\/ \u6211\u4eec\u671f\u671b\u6765\u81ea\u670d\u52a1\u5668\u7684\u56de\u7b54\u770b\u8d77\u6765\u50cf\u8fd9\u6837\uff1a\ngotWeather({\n  temperature: 25,\n  humidity: 78\n});\n<\/code><\/pre>\n<ol start=\"4\">\n<li>\u5f53\u8fdc\u7a0b\u811a\u672c\u52a0\u8f7d\u5e76\u6267\u884c\u65f6\uff0c<code>gotWeather<\/code>\u00a0\u51fd\u6570\u5c06\u8fd0\u884c\uff0c\u5e76\u4e14\u56e0\u4e3a\u5b83\u662f\u6211\u4eec\u7684\u51fd\u6570\uff0c\u6211\u4eec\u5c31\u6709\u4e86\u9700\u8981\u7684\u6570\u636e\u3002<br \/>\n\u8fd9\u662f\u53ef\u884c\u7684\uff0c\u5e76\u4e14\u4e0d\u8fdd\u53cd\u5b89\u5168\u89c4\u5b9a\uff0c\u56e0\u4e3a\u53cc\u65b9\u90fd\u540c\u610f\u4ee5\u8fd9\u79cd\u65b9\u5f0f\u4f20\u9012\u6570\u636e\u3002\u800c\u4e14\uff0c\u65e2\u7136\u53cc\u65b9\u90fd\u540c\u610f\u8fd9\u79cd\u884c\u4e3a\uff0c\u90a3\u8fd9\u80af\u5b9a\u4e0d\u662f\u9ed1\u5ba2\u653b\u51fb\u4e86\u3002\u73b0\u5728\u4ecd\u7136\u6709\u63d0\u4f9b\u8fd9\u79cd\u8bbf\u95ee\u7684\u670d\u52a1\uff0c\u56e0\u4e3a\u5373\u4f7f\u662f\u975e\u5e38\u65e7\u7684\u6d4f\u89c8\u5668\u5b83\u4f9d\u7136\u9002\u7528\u3002<br \/>\n\u4e0d\u4e45\u4e4b\u540e\uff0c\u7f51\u7edc\u65b9\u6cd5\u51fa\u73b0\u5728\u4e86\u6d4f\u89c8\u5668 JavaScript \u4e2d\u3002<br \/>\n\u8d77\u521d\uff0c\u8de8\u6e90\u8bf7\u6c42\u662f\u88ab\u7981\u6b62\u7684\u3002\u4f46\u662f\uff0c\u7ecf\u8fc7\u957f\u65f6\u95f4\u7684\u8ba8\u8bba\uff0c\u8de8\u6e90\u8bf7\u6c42\u88ab\u5141\u8bb8\u4e86\uff0c\u4f46\u662f\u4efb\u4f55\u65b0\u529f\u80fd\u90fd\u9700\u8981\u670d\u52a1\u5668\u660e\u786e\u5141\u8bb8\uff0c\u4ee5\u7279\u6b8a\u7684 header \u8868\u8ff0\u3002<\/li>\n<\/ol>\n<h2>\u5b89\u5168\u8bf7\u6c42<\/h2>\n<p>\u6709\u4e24\u79cd\u7c7b\u578b\u7684\u8de8\u6e90\u8bf7\u6c42\uff1a<\/p>\n<ol>\n<li>\u5b89\u5168\u8bf7\u6c42\u3002<\/li>\n<li>\u6240\u6709\u5176\u4ed6\u8bf7\u6c42\u3002<br \/>\n\u5b89\u5168\u8bf7\u6c42\u5f88\u7b80\u5355\uff0c\u6240\u4ee5\u6211\u4eec\u5148\u4ece\u5b83\u5f00\u59cb\u3002<br \/>\n\u5982\u679c\u4e00\u4e2a\u8bf7\u6c42\u6ee1\u8db3\u4e0b\u9762\u8fd9\u4e24\u4e2a\u6761\u4ef6\uff0c\u5219\u8be5\u8bf7\u6c42\u662f\u5b89\u5168\u7684\uff1a<\/li>\n<li><a href=\"https:\/\/fetch.spec.whatwg.org\/#cors-safelisted-method\">\u5b89\u5168\u7684\u65b9\u6cd5<\/a>\uff1aGET\uff0cPOST \u6216 HEAD<\/li>\n<li><a href=\"https:\/\/fetch.spec.whatwg.org\/#cors-safelisted-request-header\">\u5b89\u5168\u7684 header<\/a>\u00a0\u2014\u2014 \u4ec5\u5141\u8bb8\u81ea\u5b9a\u4e49\u4e0b\u5217 header\uff1a\n<ul>\n<li><code>Accept<\/code>\uff0c<\/li>\n<li><code>Accept-Language<\/code>\uff0c<\/li>\n<li><code>Content-Language<\/code>\uff0c<\/li>\n<li><code>Content-Type<\/code>\u00a0\u7684\u503c\u4e3a\u00a0<code>application\/x-www-form-urlencoded<\/code>\uff0c<code>multipart\/form-data<\/code>\u00a0\u6216\u00a0<code>text\/plain<\/code>\u3002<br \/>\n\u4efb\u4f55\u5176\u4ed6\u8bf7\u6c42\u90fd\u88ab\u8ba4\u4e3a\u662f\u201c\u975e\u5b89\u5168\u201d\u8bf7\u6c42\u3002\u4f8b\u5982\uff0c\u5177\u6709\u00a0<code>PUT<\/code>\u00a0\u65b9\u6cd5\u6216\u00a0<code>API-Key<\/code>\u00a0HTTP-header \u7684\u8bf7\u6c42\u5c31\u4e0d\u662f\u5b89\u5168\u8bf7\u6c42\u3002<br \/>\n<strong>\u672c\u8d28\u533a\u522b\u5728\u4e8e\uff0c\u53ef\u4ee5\u4f7f\u7528\u00a0<code>&lt;form&gt;<\/code>\u00a0\u6216\u00a0<code>&lt;script&gt;<\/code>\u00a0\u8fdb\u884c\u5b89\u5168\u8bf7\u6c42\uff0c\u800c\u65e0\u9700\u4efb\u4f55\u5176\u4ed6\u7279\u6b8a\u65b9\u6cd5\u3002<\/strong><br \/>\n\u56e0\u6b64\uff0c\u5373\u4f7f\u662f\u975e\u5e38\u65e7\u7684\u670d\u52a1\u5668\u4e5f\u80fd\u5f88\u597d\u5730\u63a5\u6536\u5b89\u5168\u8bf7\u6c42\u3002<br \/>\n\u4e0e\u6b64\u76f8\u53cd\uff0c\u5e26\u6709\u975e\u6807\u51c6 header \u6216\u8005\u4f8b\u5982\u00a0<code>DELETE<\/code>\u00a0\u65b9\u6cd5\u7684\u8bf7\u6c42\uff0c\u65e0\u6cd5\u901a\u8fc7\u8fd9\u79cd\u65b9\u5f0f\u521b\u5efa\u3002\u5728\u5f88\u957f\u4e00\u6bb5\u65f6\u95f4\u91cc\uff0cJavaScript \u90fd\u4e0d\u80fd\u8fdb\u884c\u8fd9\u6837\u7684\u8bf7\u6c42\u3002\u6240\u4ee5\uff0c\u65e7\u7684\u670d\u52a1\u5668\u53ef\u80fd\u4f1a\u8ba4\u4e3a\u6b64\u7c7b\u8bf7\u6c42\u6765\u81ea\u5177\u6709\u7279\u6743\u7684\u6765\u6e90\uff08privileged source\uff09\uff0c\u201c\u56e0\u4e3a\u7f51\u9875\u65e0\u6cd5\u53d1\u9001\u5b83\u4eec\u201d\u3002<br \/>\n\u5f53\u6211\u4eec\u5c1d\u8bd5\u53d1\u9001\u4e00\u4e2a\u975e\u5b89\u5168\u8bf7\u6c42\u65f6\uff0c\u6d4f\u89c8\u5668\u4f1a\u53d1\u9001\u4e00\u4e2a\u7279\u6b8a\u7684\u201c\u9884\u68c0\uff08preflight\uff09\u201d\u8bf7\u6c42\u5230\u670d\u52a1\u5668 \u2014\u2014 \u8be2\u95ee\u670d\u52a1\u5668\uff0c\u4f60\u63a5\u53d7\u6b64\u7c7b\u8de8\u6e90\u8bf7\u6c42\u5417\uff1f<br \/>\n\u5e76\u4e14\uff0c\u9664\u975e\u670d\u52a1\u5668\u660e\u786e\u901a\u8fc7 header \u8fdb\u884c\u786e\u8ba4\uff0c\u5426\u5219\u975e\u5b89\u5168\u8bf7\u6c42\u4e0d\u4f1a\u88ab\u53d1\u9001\u3002<br \/>\n\u73b0\u5728\uff0c\u6211\u4eec\u6765\u8be6\u7ec6\u4ecb\u7ecd\u5b83\u4eec\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<h2>\u7528\u4e8e\u5b89\u5168\u8bf7\u6c42\u7684 CORS<\/h2>\n<p>\u5982\u679c\u4e00\u4e2a\u8bf7\u6c42\u662f\u8de8\u6e90\u7684\uff0c\u6d4f\u89c8\u5668\u59cb\u7ec8\u4f1a\u5411\u5176\u6dfb\u52a0\u00a0<code>Origin<\/code>\u00a0header\u3002<br \/>\n\u4f8b\u5982\uff0c\u5982\u679c\u6211\u4eec\u4ece\u00a0<code>https:\/\/javascript.info\/page<\/code>\u00a0\u8bf7\u6c42\u00a0<code>https:\/\/anywhere.com\/request<\/code>\uff0c\u8bf7\u6c42\u7684 header \u5c06\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<pre><code class=\"language-PlainText\">GET \/request\nHost: anywhere.com\nOrigin: https:\/\/javascript.info\n...\n<\/code><\/pre>\n<p>\u6b63\u5982\u4f60\u6240\u770b\u5230\u7684\uff0c<code>Origin<\/code>\u00a0\u5305\u542b\u4e86\u786e\u5207\u7684\u6e90\uff08domain\/protocol\/port\uff09\uff0c\u6ca1\u6709\u8def\u5f84\uff08path\uff09\u3002<br \/>\n\u670d\u52a1\u5668\u53ef\u4ee5\u68c0\u67e5\u00a0<code>Origin<\/code>\uff0c\u5982\u679c\u540c\u610f\u63a5\u53d7\u8fd9\u6837\u7684\u8bf7\u6c42\uff0c\u5c31\u4f1a\u5728\u54cd\u5e94\u4e2d\u6dfb\u52a0\u4e00\u4e2a\u7279\u6b8a\u7684 header\u00a0<code>Access-Control-Allow-Origin<\/code>\u3002\u8be5 header \u5305\u542b\u4e86\u5141\u8bb8\u7684\u6e90\uff08\u5728\u6211\u4eec\u7684\u793a\u4f8b\u4e2d\u662f\u00a0<code>https:\/\/javascript.info<\/code>\uff09\uff0c\u6216\u8005\u4e00\u4e2a\u661f\u53f7\u00a0<code>*<\/code>\u3002\u7136\u540e\u54cd\u5e94\u6210\u529f\uff0c\u5426\u5219\u62a5\u9519<br \/>\n\u6d4f\u89c8\u5668\u5728\u8fd9\u91cc\u626e\u6f14\u53d7\u88ab\u4fe1\u4efb\u7684\u4e2d\u95f4\u4eba\u7684\u89d2\u8272\uff1a<\/p>\n<ol>\n<li>\u5b83\u786e\u4fdd\u53d1\u9001\u7684\u8de8\u6e90\u8bf7\u6c42\u5e26\u6709\u6b63\u786e\u7684\u00a0<code>Origin<\/code>\u3002<\/li>\n<li>\u5b83\u68c0\u67e5\u54cd\u5e94\u4e2d\u7684\u8bb8\u53ef\u00a0<code>Access-Control-Allow-Origin<\/code>\uff0c\u5982\u679c\u5b58\u5728\uff0c\u5219\u5141\u8bb8 JavaScript \u8bbf\u95ee\u54cd\u5e94\uff0c\u5426\u5219\u5c06\u5931\u8d25\u5e76\u62a5\u9519\u3002<br \/>\n<div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240630192520-4.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  decoding=\"async\" data-original=\"https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240630192520-4.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"Pasted image 20240630192520.png\"><\/div><br \/>\n\u8fd9\u662f\u4e00\u4e2a\u5e26\u6709\u670d\u52a1\u5668\u8bb8\u53ef\u7684\u54cd\u5e94\u793a\u4f8b\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-PlainText\">200 OK\nContent-Type:text\/html; charset=UTF-8\nAccess-Control-Allow-Origin: https:\/\/javascript.info\n<\/code><\/pre>\n<h2>Response header<\/h2>\n<p>\u5bf9\u4e8e\u8de8\u6e90\u8bf7\u6c42\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cJavaScript \u53ea\u80fd\u8bbf\u95ee\u201c\u5b89\u5168\u7684\u201d response header\uff1a<\/p>\n<ul>\n<li><code>Cache-Control<\/code><\/li>\n<li><code>Content-Language<\/code><\/li>\n<li><code>Content-Type<\/code><\/li>\n<li><code>Expires<\/code><\/li>\n<li><code>Last-Modified<\/code><\/li>\n<li><code>Pragma<\/code><br \/>\n\u8bbf\u95ee\u4efb\u4f55\u5176\u4ed6 response header \u90fd\u5c06\u5bfc\u81f4 error\u3002<\/li>\n<\/ul>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u8bf7\u6ce8\u610f\uff1a\u5217\u8868\u4e2d\u6ca1\u6709\u00a0<code>Content-Length<\/code>\u00a0header\uff01<br \/>\n\u8be5 header \u5305\u542b\u5b8c\u6574\u7684\u54cd\u5e94\u957f\u5ea6\u3002\u56e0\u6b64\uff0c\u5982\u679c\u6211\u4eec\u6b63\u5728\u4e0b\u8f7d\u67d0\u4e9b\u5185\u5bb9\uff0c\u5e76\u5e0c\u671b\u8ddf\u8e2a\u8fdb\u5ea6\u767e\u5206\u6bd4\uff0c\u5219\u9700\u8981\u989d\u5916\u7684\u6743\u9650\u624d\u80fd\u8bbf\u95ee\u8be5 header\uff08\u8bf7\u89c1\u4e0b\u6587\uff09\u3002<\/p>\n<\/blockquote>\n<p>\u8981\u6388\u4e88 JavaScript \u5bf9\u4efb\u4f55\u5176\u4ed6 response header \u7684\u8bbf\u95ee\u6743\u9650\uff0c\u670d\u52a1\u5668\u5fc5\u987b\u53d1\u9001\u00a0<code>Access-Control-Expose-Headers<\/code>\u00a0header\u3002\u5b83\u5305\u542b\u4e00\u4e2a\u4ee5\u9017\u53f7\u5206\u9694\u7684\u5e94\u8be5\u88ab\u8bbe\u7f6e\u4e3a\u53ef\u8bbf\u95ee\u7684\u975e\u5b89\u5168 header \u540d\u79f0\u5217\u8868\u3002<br \/>\n\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">200 OK\nContent-Type:text\/html; charset=UTF-8\nContent-Length: 12345\nAPI-Key: 2c9de507f2c54aa1\nAccess-Control-Allow-Origin: https:\/\/javascript.info\nAccess-Control-Expose-Headers: Content-Length,API-Key\n<\/code><\/pre>\n<p>\u6709\u4e86\u8fd9\u79cd\u00a0<code>Access-Control-Expose-Headers<\/code>\u00a0header\uff0c\u6b64\u811a\u672c\u5c31\u88ab\u5141\u8bb8\u8bfb\u53d6\u54cd\u5e94\u7684\u00a0<code>Content-Length<\/code>\u00a0\u548c\u00a0<code>API-Key<\/code>\u00a0header\u3002<\/p>\n<h2>\u201c\u975e\u5b89\u5168\u201d\u8bf7\u6c42<\/h2>\n<p>\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4efb\u4f55 HTTP \u65b9\u6cd5\uff1a\u4e0d\u4ec5\u4ec5\u662f\u00a0<code>GET\/POST<\/code>\uff0c\u4e5f\u53ef\u4ee5\u662f\u00a0<code>PATCH<\/code>\uff0c<code>DELETE<\/code>\u00a0\u53ca\u5176\u4ed6\u3002<br \/>\n\u4e4b\u524d\uff0c\u6ca1\u6709\u4eba\u80fd\u591f\u8bbe\u60f3\u7f51\u9875\u80fd\u53d1\u51fa\u8fd9\u6837\u7684\u8bf7\u6c42\u3002\u56e0\u6b64\uff0c\u53ef\u80fd\u4ecd\u7136\u5b58\u5728\u6709\u4e9b Web \u670d\u52a1\u5c06\u975e\u6807\u51c6\u65b9\u6cd5\u89c6\u4e3a\u4e00\u4e2a\u4fe1\u53f7\uff1a\u201c\u8fd9\u4e0d\u662f\u6d4f\u89c8\u5668\u201d\u3002\u5b83\u4eec\u53ef\u4ee5\u5728\u68c0\u67e5\u8bbf\u95ee\u6743\u9650\u65f6\u5c06\u5176\u8003\u8651\u5728\u5185\u3002<br \/>\n\u56e0\u6b64\uff0c\u4e3a\u4e86\u907f\u514d\u8bef\u89e3\uff0c\u4efb\u4f55\u201c\u975e\u5b89\u5168\u201d\u8bf7\u6c42 \u2014\u2014 \u5728\u8fc7\u53bb\u65e0\u6cd5\u5b8c\u6210\u7684\uff0c\u6d4f\u89c8\u5668\u4e0d\u4f1a\u7acb\u5373\u53d1\u51fa\u6b64\u7c7b\u8bf7\u6c42\u3002\u9996\u5148\uff0c\u5b83\u4f1a\u5148\u53d1\u9001\u4e00\u4e2a\u521d\u6b65\u7684\u3001\u6240\u8c13\u7684\u201c\u9884\u68c0\uff08preflight\uff09\u201d\u8bf7\u6c42\uff0c\u6765\u8bf7\u6c42\u8bb8\u53ef\u3002<br \/>\n\u9884\u68c0\u8bf7\u6c42\u4f7f\u7528\u00a0<code>OPTIONS<\/code>\u00a0\u65b9\u6cd5\uff0c\u5b83\u6ca1\u6709 body\uff0c\u4f46\u662f\u6709\u4e09\u4e2a header\uff1a<\/p>\n<ul>\n<li><code>Access-Control-Request-Method<\/code>\u00a0header \u5e26\u6709\u975e\u5b89\u5168\u8bf7\u6c42\u7684\u65b9\u6cd5\u3002<\/li>\n<li><code>Access-Control-Request-Headers<\/code>\u00a0header \u63d0\u4f9b\u4e00\u4e2a\u4ee5\u9017\u53f7\u5206\u9694\u7684\u975e\u5b89\u5168 HTTP-header \u5217\u8868\u3002<br \/>\n\u5982\u679c\u670d\u52a1\u5668\u540c\u610f\u5904\u7406\u8bf7\u6c42\uff0c\u90a3\u4e48\u5b83\u4f1a\u8fdb\u884c\u54cd\u5e94\uff0c\u6b64\u54cd\u5e94\u7684\u72b6\u6001\u7801\u5e94\u8be5\u4e3a 200\uff0c\u6ca1\u6709 body\uff0c\u5177\u6709 header\uff1a<\/li>\n<li><code>Access-Control-Allow-Origin<\/code>\u00a0\u5fc5\u987b\u4e3a\u00a0<code>*<\/code>\u00a0\u6216\u8fdb\u884c\u8bf7\u6c42\u7684\u6e90\uff08\u4f8b\u5982\u00a0<code>https:\/\/javascript.info<\/code>\uff09\u624d\u80fd\u5141\u8bb8\u6b64\u8bf7\u6c42\u3002<\/li>\n<li><code>Access-Control-Allow-Methods<\/code>\u00a0\u5fc5\u987b\u5177\u6709\u5141\u8bb8\u7684\u65b9\u6cd5\u3002<\/li>\n<li><code>Access-Control-Allow-Headers<\/code>\u00a0\u5fc5\u987b\u5177\u6709\u4e00\u4e2a\u5141\u8bb8\u7684 header \u5217\u8868\u3002<\/li>\n<li>\u53e6\u5916\uff0cheader\u00a0<code>Access-Control-Max-Age<\/code>\u00a0\u53ef\u4ee5\u6307\u5b9a\u7f13\u5b58\u6b64\u6743\u9650\u7684\u79d2\u6570\u3002\u56e0\u6b64\uff0c\u6d4f\u89c8\u5668\u4e0d\u662f\u5fc5\u987b\u4e3a\u6ee1\u8db3\u7ed9\u5b9a\u6743\u9650\u7684\u540e\u7eed\u8bf7\u6c42\u53d1\u9001\u9884\u68c0\u3002<br \/>\n<div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240630192818-4.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  decoding=\"async\" data-original=\"https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240630192818-4.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"Pasted image 20240630192818.png\"><\/div><br \/>\n\u8ba9\u6211\u4eec\u5728\u4e00\u4e2a\u8de8\u6e90\u00a0<code>PATCH<\/code>\u00a0\u8bf7\u6c42\u7684\u4f8b\u5b50\u4e2d\u4e00\u6b65\u4e00\u6b65\u5730\u770b\u5b83\u662f\u5982\u4f55\u5de5\u4f5c\u7684\uff08\u6b64\u65b9\u6cd5\u7ecf\u5e38\u88ab\u7528\u4e8e\u66f4\u65b0\u6570\u636e\uff09\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let response = await fetch('https:\/\/site.com\/service.json', {\n  method: 'PATCH',\n  headers: {\n    'Content-Type': 'application\/json',\n    'API-Key': 'secret'\n  }\n});\n<\/code><\/pre>\n<p>\u8fd9\u91cc\u6709\u4e09\u4e2a\u7406\u7531\u89e3\u91ca\u4e3a\u4ec0\u4e48\u5b83\u4e0d\u662f\u4e00\u4e2a\u5b89\u5168\u8bf7\u6c42\uff08\u5176\u5b9e\u4e00\u4e2a\u5c31\u591f\u4e86\uff09\uff1a<\/p>\n<ul>\n<li>\u65b9\u6cd5\u00a0<code>PATCH<\/code><\/li>\n<li><code>Content-Type<\/code>\u00a0\u4e0d\u662f\u8fd9\u4e09\u4e2a\u4e2d\u4e4b\u4e00\uff1a<code>application\/x-www-form-urlencoded<\/code>\uff0c<code>multipart\/form-data<\/code>\uff0c<code>text\/plain<\/code>\u3002<\/li>\n<li>\u201c\u975e\u5b89\u5168\u201d\u00a0<code>API-Key<\/code>\u00a0header\u3002<\/li>\n<\/ul>\n<h3>Step 1 \u9884\u68c0\u8bf7\u6c42\uff08preflight request\uff09<\/h3>\n<p>\u5728\u53d1\u9001\u6211\u4eec\u7684\u8bf7\u6c42\u524d\uff0c\u6d4f\u89c8\u5668\u4f1a\u81ea\u5df1\u53d1\u9001\u5982\u4e0b\u6240\u793a\u7684\u9884\u68c0\u8bf7\u6c42\uff1a<\/p>\n<pre><code class=\"language-PlainText\">OPTIONS \/service.json\nHost: site.com\nOrigin: https:\/\/javascript.info\nAccess-Control-Request-Method: PATCH\nAccess-Control-Request-Headers: Content-Type,API-Key\n<\/code><\/pre>\n<ul>\n<li>\u65b9\u6cd5\uff1a<code>OPTIONS<\/code>\u3002<\/li>\n<li>\u8def\u5f84 \u2014\u2014 \u4e0e\u4e3b\u8bf7\u6c42\u5b8c\u5168\u76f8\u540c\uff1a<code>\/service.json<\/code>\u3002<\/li>\n<li>\u7279\u6b8a\u8de8\u6e90\u5934\uff1a\n<ul>\n<li><code>Origin<\/code>\u00a0\u2014\u2014 \u6765\u6e90\u3002<\/li>\n<li><code>Access-Control-Request-Method<\/code>\u00a0\u2014\u2014 \u8bf7\u6c42\u65b9\u6cd5\u3002<\/li>\n<li><code>Access-Control-Request-Headers<\/code>\u00a0\u2014\u2014 \u4ee5\u9017\u53f7\u5206\u9694\u7684\u201c\u975e\u5b89\u5168\u201d header \u5217\u8868\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>Step 2 \u9884\u68c0\u54cd\u5e94\uff08preflight response\uff09<\/h3>\n<p>\u670d\u52a1\u5e94\u54cd\u5e94\u72b6\u6001 200 \u548c header\uff1a<\/p>\n<ul>\n<li><code>Access-Control-Allow-Origin: https:\/\/javascript.info<\/code><\/li>\n<li><code>Access-Control-Allow-Methods: PATCH<\/code><\/li>\n<li><code>Access-Control-Allow-Headers: Content-Type,API-Key<\/code>\u3002<br \/>\n\u8fd9\u5c06\u5141\u8bb8\u540e\u7eed\u901a\u4fe1\uff0c\u5426\u5219\u4f1a\u89e6\u53d1\u9519\u8bef\u3002<br \/>\n\u5982\u679c\u670d\u52a1\u5668\u5c06\u6765\u9700\u8981\u5176\u4ed6\u65b9\u6cd5\u548c header\uff0c\u5219\u53ef\u4ee5\u901a\u8fc7\u5c06\u8fd9\u4e9b\u65b9\u6cd5\u548c header \u6dfb\u52a0\u5230\u5217\u8868\u4e2d\u6765\u9884\u5148\u5141\u8bb8\u5b83\u4eec\u3002<br \/>\n\u4f8b\u5982\uff0c\u6b64\u54cd\u5e94\u8fd8\u5141\u8bb8\u00a0<code>PUT<\/code>\u3001<code>DELETE<\/code>\u00a0\u4ee5\u53ca\u5176\u4ed6 header\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-PlainText\">200 OK\nAccess-Control-Allow-Origin: https:\/\/javascript.info\nAccess-Control-Allow-Methods: PUT,PATCH,DELETE\nAccess-Control-Allow-Headers: API-Key,Content-Type,If-Modified-Since,Cache-Control\nAccess-Control-Max-Age: 86400\n<\/code><\/pre>\n<p>\u73b0\u5728\uff0c\u6d4f\u89c8\u5668\u53ef\u4ee5\u770b\u5230\u00a0<code>PATCH<\/code>\u00a0\u5728\u00a0<code>Access-Control-Allow-Methods<\/code>\u00a0\u4e2d\uff0c<code>Content-Type,API-Key<\/code>\u00a0\u5728\u5217\u8868\u00a0<code>Access-Control-Allow-Headers<\/code>\u00a0\u4e2d\uff0c\u56e0\u6b64\u5b83\u5c06\u53d1\u9001\u4e3b\u8bf7\u6c42\u3002<br \/>\n\u5982\u679c\u00a0<code>Access-Control-Max-Age<\/code>\u00a0\u5e26\u6709\u4e00\u4e2a\u8868\u793a\u79d2\u7684\u6570\u5b57\uff0c\u5219\u5728\u7ed9\u5b9a\u7684\u65f6\u95f4\u5185\uff0c\u9884\u68c0\u6743\u9650\u4f1a\u88ab\u7f13\u5b58\u3002\u4e0a\u9762\u7684\u54cd\u5e94\u5c06\u88ab\u7f13\u5b58 86400 \u79d2\uff0c\u4e5f\u5c31\u662f\u4e00\u5929\u3002\u5728\u6b64\u65f6\u95f4\u8303\u56f4\u5185\uff0c\u540e\u7eed\u8bf7\u6c42\u5c06\u4e0d\u4f1a\u89e6\u53d1\u9884\u68c0\u3002\u5047\u8bbe\u5b83\u4eec\u7b26\u5408\u7f13\u5b58\u7684\u914d\u989d\uff0c\u5219\u5c06\u76f4\u63a5\u53d1\u9001\u5b83\u4eec\u3002<\/p>\n<h3>Step 3 \u5b9e\u9645\u8bf7\u6c42\uff08actual request\uff09<\/h3>\n<p>\u9884\u68c0\u6210\u529f\u540e\uff0c\u6d4f\u89c8\u5668\u73b0\u5728\u53d1\u51fa\u4e3b\u8bf7\u6c42\u3002\u8fd9\u91cc\u7684\u8fc7\u7a0b\u4e0e\u5b89\u5168\u8bf7\u6c42\u7684\u8fc7\u7a0b\u76f8\u540c\u3002<br \/>\n\u4e3b\u8bf7\u6c42\u5177\u6709\u00a0<code>Origin<\/code>\u00a0header\uff08\u56e0\u4e3a\u5b83\u662f\u8de8\u6e90\u7684\uff09\uff1a<\/p>\n<pre><code class=\"language-PlainText\">PATCH \/service.json\nHost: site.com\nContent-Type: application\/json\nAPI-Key: secret\nOrigin: https:\/\/javascript.info\n<\/code><\/pre>\n<h3>Step 4 \u5b9e\u9645\u54cd\u5e94\uff08actual response\uff09<\/h3>\n<p>\u670d\u52a1\u5668\u4e0d\u5e94\u8be5\u5fd8\u8bb0\u5728\u4e3b\u54cd\u5e94\u4e2d\u6dfb\u52a0\u00a0<code>Access-Control-Allow-Origin<\/code>\u3002\u6210\u529f\u7684\u9884\u68c0\u5e76\u4e0d\u80fd\u514d\u9664\u6b64\u8981\u6c42\uff1a<\/p>\n<pre><code class=\"language-PlainText\">Access-Control-Allow-Origin: https:\/\/javascript.info\n<\/code><\/pre>\n<p>\u7136\u540e\uff0cJavaScript \u53ef\u4ee5\u8bfb\u53d6\u4e3b\u670d\u52a1\u5668\u54cd\u5e94\u4e86\u3002<\/p>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u9884\u68c0\u8bf7\u6c42\u53d1\u751f\u5728\u201c\u5e55\u540e\u201d\uff0c\u5b83\u5bf9 JavaScript \u4e0d\u53ef\u89c1\u3002<br \/>\nJavaScript \u4ec5\u83b7\u53d6\u5bf9\u4e3b\u8bf7\u6c42\u7684\u54cd\u5e94\uff0c\u5982\u679c\u6ca1\u6709\u670d\u52a1\u5668\u8bb8\u53ef\uff0c\u5219\u83b7\u5f97\u4e00\u4e2a error\u3002<\/p>\n<\/blockquote>\n<h2>\u51ed\u636e\uff08Credentials\uff09<\/h2>\n<p>\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u7531 JavaScript \u4ee3\u7801\u53d1\u8d77\u7684\u8de8\u6e90\u8bf7\u6c42\u4e0d\u4f1a\u5e26\u6765\u4efb\u4f55\u51ed\u636e\uff08cookies \u6216\u8005 HTTP \u8ba4\u8bc1\uff08HTTP authentication\uff09\uff09\u3002<br \/>\n\u8fd9\u5bf9\u4e8e HTTP \u8bf7\u6c42\u6765\u8bf4\u5e76\u4e0d\u5e38\u89c1\u3002\u901a\u5e38\uff0c\u5bf9\u00a0<code>http:\/\/site.com<\/code>\u00a0\u7684\u8bf7\u6c42\u9644\u5e26\u6709\u8be5\u57df\u7684\u6240\u6709 cookie\u3002\u4f46\u662f\u7531 JavaScript \u65b9\u6cd5\u53d1\u51fa\u7684\u8de8\u6e90\u8bf7\u6c42\u662f\u4e2a\u4f8b\u5916\u3002<br \/>\n\u4f8b\u5982\uff0c<code>fetch('http:\/\/another.com')<\/code>\u00a0\u4e0d\u4f1a\u53d1\u9001\u4efb\u4f55 cookie\uff0c\u5373\u4f7f\u90a3\u4e9b (!) \u5c5e\u4e8e\u00a0<code>another.com<\/code>\u00a0\u57df\u7684 cookie\u3002<br \/>\n\u4e3a\u4ec0\u4e48\uff1f<br \/>\n\u8fd9\u662f\u56e0\u4e3a\u5177\u6709\u51ed\u636e\u7684\u8bf7\u6c42\u6bd4\u6ca1\u6709\u51ed\u636e\u7684\u8bf7\u6c42\u8981\u5f3a\u5927\u5f97\u591a\u3002\u5982\u679c\u88ab\u5141\u8bb8\uff0c\u5b83\u4f1a\u4f7f\u7528\u5b83\u4eec\u7684\u51ed\u636e\u6388\u4e88 JavaScript \u4ee3\u8868\u7528\u6237\u884c\u4e3a\u548c\u8bbf\u95ee\u654f\u611f\u4fe1\u606f\u7684\u5168\u90e8\u6743\u529b\u3002<br \/>\n\u670d\u52a1\u5668\u771f\u7684\u8fd9\u4e48\u4fe1\u4efb\u8fd9\u79cd\u811a\u672c\u5417\uff1f\u662f\u7684\uff0c\u5b83\u5fc5\u987b\u663e\u5f0f\u5730\u5e26\u6709\u5141\u8bb8\u8bf7\u6c42\u7684\u51ed\u636e\u548c\u9644\u52a0 header\u3002<br \/>\n\u8981\u5728\u00a0<code>fetch<\/code>\u00a0\u4e2d\u53d1\u9001\u51ed\u636e\uff0c\u6211\u4eec\u9700\u8981\u6dfb\u52a0\u00a0<code>credentials: &quot;include&quot;<\/code>\u00a0\u9009\u9879\uff0c\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">fetch('http:\/\/another.com', {\n  credentials: &quot;include&quot;\n});\n<\/code><\/pre>\n<p>\u73b0\u5728\uff0c<code>fetch<\/code>\u00a0\u5c06\u628a\u6e90\u81ea\u00a0<code>another.com<\/code>\u00a0\u7684 cookie \u548c\u6211\u4eec\u7684\u8bf7\u6c42\u53d1\u9001\u5230\u8be5\u7f51\u7ad9\u3002<br \/>\n\u5982\u679c\u670d\u52a1\u5668\u540c\u610f\u63a5\u53d7\u00a0<strong>\u5e26\u6709\u51ed\u636e<\/strong>\u00a0\u7684\u8bf7\u6c42\uff0c\u5219\u9664\u4e86\u00a0<code>Access-Control-Allow-Origin<\/code>\u00a0\u5916\uff0c\u670d\u52a1\u5668\u8fd8\u5e94\u8be5\u5728\u54cd\u5e94\u4e2d\u6dfb\u52a0 header\u00a0<code>Access-Control-Allow-Credentials: true<\/code>\u3002<br \/>\n\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-PlainText\">200 OK\nAccess-Control-Allow-Origin: https:\/\/javascript.info\nAccess-Control-Allow-Credentials: true\n<\/code><\/pre>\n<p>\u8bf7\u6ce8\u610f\uff1a\u5bf9\u4e8e\u5177\u6709\u51ed\u636e\u7684\u8bf7\u6c42\uff0c\u7981\u6b62\u00a0<code>Access-Control-Allow-Origin<\/code>\u00a0\u4f7f\u7528\u661f\u53f7\u00a0<code>*<\/code>\u3002\u5982\u4e0a\u6240\u793a\uff0c\u5b83\u5fc5\u987b\u6709\u4e00\u4e2a\u786e\u5207\u7684\u6e90\u3002\u8fd9\u662f\u53e6\u4e00\u9879\u5b89\u5168\u63aa\u65bd\uff0c\u4ee5\u786e\u4fdd\u670d\u52a1\u5668\u771f\u7684\u77e5\u9053\u5b83\u4fe1\u4efb\u7684\u53d1\u51fa\u6b64\u8bf7\u6c42\u7684\u662f\u8c01\u3002<\/p>\n<h1>Fetch API<\/h1>\n<p>\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6211\u4eec\u5df2\u7ecf\u5bf9\u00a0<code>fetch<\/code>\u00a0\u76f8\u5f53\u4e86\u89e3\u4e86\u3002<br \/>\n\u73b0\u5728\u8ba9\u6211\u4eec\u6765\u770b\u770b\u00a0<code>fetch<\/code>\u00a0\u7684\u5269\u4f59 API\uff0c\u6765\u4e86\u89e3\u5b83\u7684\u5168\u90e8\u672c\u9886\u5427\u3002<\/p>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u8bf7\u6ce8\u610f\uff1a\u8fd9\u4e9b\u9009\u9879 (option) \u5927\u591a\u90fd\u5f88\u5c11\u4f7f\u7528\u3002\u5373\u4f7f\u8df3\u8fc7\u672c\u7ae0\uff0c\u4f60\u4e5f\u53ef\u4ee5\u5f88\u597d\u5730\u4f7f\u7528\u00a0<code>fetch<\/code>\u3002<br \/>\n\u4f46\u662f\uff0c\u77e5\u9053\u00a0<code>fetch<\/code>\u00a0\u53ef\u4ee5\u505a\u4ec0\u4e48\u8fd8\u662f\u5f88\u597d\u7684\uff0c\u6240\u4ee5\u5982\u679c\u9700\u8981\uff0c\u4f60\u53ef\u4ee5\u6765\u770b\u770b\u8fd9\u4e9b\u7ec6\u8282\u5185\u5bb9\u3002<\/p>\n<\/blockquote>\n<p>\u8fd9\u662f\u6240\u6709\u53ef\u80fd\u7684\u00a0<code>fetch<\/code>\u00a0\u9009\u9879\u53ca\u5176\u9ed8\u8ba4\u503c\uff08\u6ce8\u91ca\u4e2d\u6807\u6ce8\u4e86\u53ef\u9009\u503c\uff09\u7684\u5b8c\u6574\u5217\u8868\uff1a<\/p>\n<pre><code class=\"language-js\">let promise = fetch(url, {\n  method: &quot;GET&quot;, \/\/ POST\uff0cPUT\uff0cDELETE\uff0c\u7b49\u3002\n  headers: {\n    \/\/ \u5185\u5bb9\u7c7b\u578b header \u503c\u901a\u5e38\u662f\u81ea\u52a8\u8bbe\u7f6e\u7684\n    \/\/ \u53d6\u51b3\u4e8e request body\n    &quot;Content-Type&quot;: &quot;text\/plain;charset=UTF-8&quot;\n  },\n  body: undefined \/\/ string\uff0cFormData\uff0cBlob\uff0cBufferSource\uff0c\u6216 URLSearchParams\n  referrer: &quot;about:client&quot;, \/\/ \u6216 &quot;&quot; \u4ee5\u4e0d\u53d1\u9001 Referer header\uff0c\n  \/\/ \u6216\u8005\u662f\u5f53\u524d\u6e90\u7684 url\n  referrerPolicy: &quot;no-referrer-when-downgrade&quot;, \/\/ no-referrer\uff0corigin\uff0csame-origin...\n  mode: &quot;cors&quot;, \/\/ same-origin\uff0cno-cors\n  credentials: &quot;same-origin&quot;, \/\/ omit\uff0cinclude\n  cache: &quot;default&quot;, \/\/ no-store\uff0creload\uff0cno-cache\uff0cforce-cache\uff0c\u6216 only-if-cached\n  redirect: &quot;follow&quot;, \/\/ manual\uff0cerror\n  integrity: &quot;&quot;, \/\/ \u4e00\u4e2a hash\uff0c\u50cf &quot;sha256-abcdef1234567890&quot;\n  keepalive: false, \/\/ true\n  signal: undefined, \/\/ AbortController \u6765\u4e2d\u6b62\u8bf7\u6c42\n  window: window \/\/ null\n});\n<\/code><\/pre>\n<p>\u4e00\u4e2a\u4ee4\u4eba\u5370\u8c61\u6df1\u523b\u7684\u5217\u8868\uff0c\u5bf9\u5427?<br \/>\n\u6211\u4eec\u5df2\u7ecf\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch\">Fetch<\/a>\u00a0\u4e00\u7ae0\u4e2d\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u00a0<code>method<\/code>\uff0c<code>headers<\/code>\u00a0\u548c\u00a0<code>body<\/code>\u3002<br \/>\n\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-abort\">Fetch\uff1a\u4e2d\u6b62\uff08Abort\uff09<\/a>\u00a0\u4e00\u7ae0\u4e2d\u4ecb\u7ecd\u4e86\u00a0<code>signal<\/code>\u00a0\u9009\u9879\u3002<br \/>\n\u73b0\u5728\u8ba9\u6211\u4eec\u4e00\u8d77\u63a2\u7d22\u5176\u4f59\u7684\u529f\u80fd\u3002<\/p>\n<h2>referrer, referrerPolicy<\/h2>\n<p>\u8fd9\u4e9b\u9009\u9879\u51b3\u5b9a\u4e86\u00a0<code>fetch<\/code>\u00a0\u5982\u4f55\u8bbe\u7f6e HTTP \u7684\u00a0<code>Referer<\/code>\u00a0header\u3002<br \/>\n\u901a\u5e38\u6765\u8bf4\uff0c\u8fd9\u4e2a header \u662f\u88ab\u81ea\u52a8\u8bbe\u7f6e\u7684\uff0c\u5e76\u5305\u542b\u4e86\u53d1\u51fa\u8bf7\u6c42\u7684\u9875\u9762\u7684 url\u3002\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u5b83\u4e00\u70b9\u4e5f\u4e0d\u91cd\u8981\uff0c\u4f46\u6709\u65f6\u51fa\u4e8e\u5b89\u5168\u8003\u8651\uff0c\u5220\u9664\u6216\u7f29\u77ed\u5b83\u662f\u6709\u610f\u4e49\u7684\u3002<br \/>\n<strong><code>referrer<\/code>\u00a0\u9009\u9879\u5141\u8bb8\u8bbe\u7f6e\u4efb\u4f55\u00a0<code>Referer<\/code>\uff08\u5728\u5f53\u524d\u57df\u7684\uff09\uff0c\u6216\u8005\u79fb\u9664\u5b83\u3002<\/strong><br \/>\n\u5982\u679c\u4e0d\u60f3\u53d1\u9001 referrer\uff0c\u53ef\u4ee5\u5c06\u00a0<code>referrer<\/code>\u00a0\u8bbe\u7f6e\u4e3a\u7a7a\u5b57\u7b26\u4e32\uff1a<\/p>\n<pre><code class=\"language-js\">fetch('\/page', {\n  referrer: &quot;&quot; \/\/ \u6ca1\u6709 Referer header\n});\n<\/code><\/pre>\n<p>\u8bbe\u7f6e\u5728\u5f53\u524d\u57df\u5185\u7684\u53e6\u4e00\u4e2a url\uff1a<\/p>\n<pre><code class=\"language-js\">fetch('\/page', {\n  \/\/ \u5047\u8bbe\u6211\u4eec\u5728 https:\/\/javascript.info\n  \/\/ \u6211\u4eec\u53ef\u4ee5\u8bbe\u7f6e\u4efb\u4f55 Referer header\uff0c\u4f46\u5fc5\u987b\u662f\u5728\u5f53\u524d\u57df\u5185\u7684\n  referrer: &quot;https:\/\/javascript.info\/anotherpage&quot;\n});\n<\/code><\/pre>\n<p><strong><code>referrerPolicy<\/code>\u00a0\u9009\u9879\u4e3a\u00a0<code>Referer<\/code>\u00a0\u8bbe\u7f6e\u4e00\u822c\u7684\u89c4\u5219\u3002<\/strong><br \/>\n\u8bf7\u6c42\u5206\u4e3a 3 \u79cd\u7c7b\u578b\uff1a<\/p>\n<ol>\n<li>\u540c\u6e90\u8bf7\u6c42\u3002<\/li>\n<li>\u8de8\u6e90\u8bf7\u6c42\u3002<\/li>\n<li>\u4ece HTTPS \u5230 HTTP \u7684\u8bf7\u6c42 (\u4ece\u5b89\u5168\u534f\u8bae\u5230\u4e0d\u5b89\u5168\u534f\u8bae)\u3002<br \/>\n\u4e0e\u00a0<code>referrer<\/code>\u00a0\u9009\u9879\u5141\u8bb8\u8bbe\u7f6e\u786e\u5207\u7684\u00a0<code>Referer<\/code>\u00a0\u503c\u4e0d\u540c\uff0c<code>referrerPolicy<\/code>\u00a0\u544a\u8bc9\u6d4f\u89c8\u5668\u9488\u5bf9\u5404\u4e2a\u8bf7\u6c42\u7c7b\u578b\u7684\u4e00\u822c\u7684\u89c4\u5219\u3002<br \/>\n\u53ef\u80fd\u7684\u503c\u5728\u00a0<a href=\"https:\/\/w3c.github.io\/webappsec-referrer-policy\/\">Referrer Policy \u89c4\u8303<\/a>\u4e2d\u6709\u8be6\u7ec6\u63cf\u8ff0\uff1a<\/li>\n<\/ol>\n<ul>\n<li><strong><code>&quot;no-referrer-when-downgrade&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u9ed8\u8ba4\u503c\uff1a\u9664\u975e\u6211\u4eec\u4ece HTTPS \u53d1\u9001\u8bf7\u6c42\u5230 HTTP\uff08\u5230\u5b89\u5168\u6027\u8f83\u4f4e\u7684\u534f\u8bae\uff09\uff0c\u5426\u5219\u59cb\u7ec8\u4f1a\u53d1\u9001\u5b8c\u6574\u7684\u00a0<code>Referer<\/code>\u3002<\/li>\n<li><strong><code>&quot;no-referrer&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u4ece\u4e0d\u53d1\u9001\u00a0<code>Referer<\/code>\u3002<\/li>\n<li><strong><code>&quot;origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u53ea\u53d1\u9001\u5728\u00a0<code>Referer<\/code>\u00a0\u4e2d\u7684\u57df\uff0c\u800c\u4e0d\u662f\u5b8c\u6574\u7684\u9875\u9762 URL\uff0c\u4f8b\u5982\uff0c\u53ea\u53d1\u9001\u00a0<code>http:\/\/site.com<\/code>\u00a0\u800c\u4e0d\u662f\u00a0<code>http:\/\/site.com\/path<\/code>\u3002<\/li>\n<li><strong><code>&quot;origin-when-cross-origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u53d1\u9001\u5b8c\u6574\u7684\u00a0<code>Referer<\/code>\u00a0\u5230\u76f8\u540c\u7684\u6e90\uff0c\u4f46\u5bf9\u4e8e\u8de8\u6e90\u8bf7\u6c42\uff0c\u53ea\u53d1\u9001\u57df\u90e8\u5206\uff08\u540c\u4e0a\uff09\u3002<\/li>\n<li><strong><code>&quot;same-origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u53d1\u9001\u5b8c\u6574\u7684\u00a0<code>Referer<\/code>\u00a0\u5230\u76f8\u540c\u7684\u6e90\uff0c\u4f46\u5bf9\u4e8e\u8de8\u6e90\u8bf7\u6c42\uff0c\u4e0d\u53d1\u9001\u00a0<code>Referer<\/code>\u3002<\/li>\n<li><strong><code>&quot;strict-origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u53ea\u53d1\u9001\u57df\uff0c\u5bf9\u4e8e HTTPS\u2192HTTP \u8bf7\u6c42\uff0c\u5219\u4e0d\u53d1\u9001\u00a0<code>Referer<\/code>\u3002<\/li>\n<li><strong><code>&quot;strict-origin-when-cross-origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u5bf9\u4e8e\u540c\u6e90\u60c5\u51b5\u4e0b\u5219\u53d1\u9001\u5b8c\u6574\u7684\u00a0<code>Referer<\/code>\uff0c\u5bf9\u4e8e\u8de8\u6e90\u60c5\u51b5\u4e0b\uff0c\u5219\u53ea\u53d1\u9001\u57df\uff0c\u5982\u679c\u662f HTTPS\u2192HTTP \u8bf7\u6c42\uff0c\u5219\u4ec0\u4e48\u90fd\u4e0d\u53d1\u9001\u3002<\/li>\n<li><strong><code>&quot;unsafe-url&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u5728\u00a0<code>Referer<\/code>\u00a0\u4e2d\u59cb\u7ec8\u53d1\u9001\u5b8c\u6574\u7684 url\uff0c\u5373\u4f7f\u662f HTTPS\u2192HTTP \u8bf7\u6c42\u3002<br \/>\n\u8fd9\u662f\u4e00\u4e2a\u5305\u542b\u6240\u6709\u7ec4\u5408\u7684\u8868\u683c\uff1a<\/li>\n<\/ul>\n<table>\n<thead>\n<tr>\n<th>\u503c<\/th>\n<th>\u540c\u6e90<\/th>\n<th>\u8de8\u6e90<\/th>\n<th>HTTPS\u2192HTTP<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><code>&quot;no-referrer&quot;<\/code><\/td>\n<td>-<\/td>\n<td>-<\/td>\n<td>-<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;no-referrer-when-downgrade&quot;<\/code>\u00a0\u6216\u00a0<code>&quot;&quot;<\/code>\uff08\u9ed8\u8ba4\uff09<\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>-<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;origin&quot;<\/code><\/td>\n<td>\u4ec5\u57df<\/td>\n<td>\u4ec5\u57df<\/td>\n<td>\u4ec5\u57df<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;origin-when-cross-origin&quot;<\/code><\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>\u4ec5\u57df<\/td>\n<td>\u4ec5\u57df<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;same-origin&quot;<\/code><\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>-<\/td>\n<td>-<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;strict-origin&quot;<\/code><\/td>\n<td>\u4ec5\u57df<\/td>\n<td>\u4ec5\u57df<\/td>\n<td>-<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;strict-origin-when-cross-origin&quot;<\/code><\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>\u4ec5\u57df<\/td>\n<td>-<\/td>\n<\/tr>\n<tr>\n<td><code>&quot;unsafe-url&quot;<\/code><\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<td>\u5b8c\u6574\u7684 url<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u5047\u5982\u6211\u4eec\u6709\u4e00\u4e2a\u5e26\u6709 URL \u7ed3\u6784\u7684\u7ba1\u7406\u533a\u57df\uff08admin zone\uff09\uff0c\u5b83\u4e0d\u5e94\u8be5\u88ab\u4ece\u7f51\u7ad9\u5916\u770b\u5230\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u53d1\u9001\u4e86\u4e00\u4e2a\u00a0<code>fetch<\/code>\uff0c\u5219\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5b83\u603b\u662f\u53d1\u9001\u5e26\u6709\u9875\u9762\u5b8c\u6574 url \u7684\u00a0<code>Referer<\/code>\u00a0header\uff08\u6211\u4eec\u4ece HTTPS \u5411 HTTP \u53d1\u9001\u8bf7\u6c42\u7684\u60c5\u51b5\u9664\u5916\uff0c\u8fd9\u79cd\u60c5\u51b5\u4e0b\u6ca1\u6709\u00a0<code>Referer<\/code>\uff09\u3002<br \/>\n\u4f8b\u5982\u00a0<code>Referer: https:\/\/javascript.info\/admin\/secret\/paths<\/code>\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u60f3\u8ba9\u5176\u4ed6\u7f51\u7ad9\u53ea\u77e5\u9053\u57df\u7684\u90e8\u5206\uff0c\u800c\u4e0d\u662f URL \u8def\u5f84\uff0c\u6211\u4eec\u53ef\u4ee5\u8fd9\u6837\u8bbe\u7f6e\u9009\u9879\uff1a<\/p>\n<pre><code class=\"language-js\">fetch('https:\/\/another.com\/page', {\n  \/\/ ...\n  referrerPolicy: &quot;origin-when-cross-origin&quot; \/\/ Referer: https:\/\/javascript.info\n});\n<\/code><\/pre>\n<p>\u6211\u4eec\u53ef\u4ee5\u5c06\u5176\u7f6e\u4e8e\u6240\u6709\u00a0<code>fetch<\/code>\u00a0\u8c03\u7528\u4e2d\uff0c\u4e5f\u53ef\u4ee5\u5c06\u5176\u96c6\u6210\u5230\u6211\u4eec\u9879\u76ee\u7684\u6267\u884c\u6240\u6709\u8bf7\u6c42\u5e76\u5728\u5185\u90e8\u4f7f\u7528\u00a0<code>fetch<\/code>\u00a0\u7684 JavaScript \u5e93\u4e2d\u3002<br \/>\n\u4e0e\u9ed8\u8ba4\u884c\u4e3a\u76f8\u6bd4\uff0c\u5b83\u7684\u552f\u4e00\u533a\u522b\u5728\u4e8e\uff0c\u5bf9\u4e8e\u8de8\u6e90\u8bf7\u6c42\uff0c<code>fetch<\/code>\u00a0\u53ea\u53d1\u9001 URL \u57df\u7684\u90e8\u5206\uff08\u4f8b\u5982\u00a0<code>https:\/\/javascript.info<\/code>\uff0c\u6ca1\u6709\u8def\u5f84\uff09\u3002\u5bf9\u4e8e\u540c\u6e90\u8bf7\u6c42\uff0c\u6211\u4eec\u4ecd\u7136\u53ef\u4ee5\u83b7\u5f97\u5b8c\u6574\u7684\u00a0<code>Referer<\/code>\uff08\u53ef\u80fd\u5bf9\u4e8e\u8c03\u8bd5\u76ee\u7684\u662f\u6709\u7528\u7684\uff09\u3002<\/p>\n<blockquote>\n<p>Referrer policy \u4e0d\u4ec5\u9002\u7528\u4e8e\u00a0<code>fetch<\/code><br \/>\n\u5728\u00a0<a href=\"https:\/\/w3c.github.io\/webappsec-referrer-policy\/\">\u89c4\u8303<\/a>\u00a0\u4e2d\u63cf\u8ff0\u7684 referrer policy\uff0c\u4e0d\u4ec5\u9002\u7528\u4e8e\u00a0<code>fetch<\/code>\uff0c\u5b83\u8fd8\u5177\u6709\u5168\u5c40\u6027\u3002<br \/>\n\u7279\u522b\u662f\uff0c\u53ef\u4ee5\u4f7f\u7528\u00a0<code>Referrer-Policy<\/code>\u00a0HTTP header\uff0c\u6216\u8005\u4e3a\u6bcf\u4e2a\u94fe\u63a5\u8bbe\u7f6e\u00a0<code>&lt;a rel=&quot;noreferrer&quot;&gt;<\/code>\uff0c\u6765\u4e3a\u6574\u4e2a\u9875\u9762\u8bbe\u7f6e\u9ed8\u8ba4\u7b56\u7565\uff08policy\uff09\u3002<\/p>\n<\/blockquote>\n<h2>mode<\/h2>\n<p><code>mode<\/code>\u00a0\u9009\u9879\u662f\u4e00\u79cd\u5b89\u5168\u63aa\u65bd\uff0c\u53ef\u4ee5\u9632\u6b62\u5076\u53d1\u7684\u8de8\u6e90\u8bf7\u6c42\uff1a<\/p>\n<ul>\n<li><strong><code>&quot;cors&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u9ed8\u8ba4\u503c\uff0c\u5141\u8bb8\u8de8\u6e90\u8bf7\u6c42\uff0c\u5982\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">Fetch\uff1a\u8de8\u6e90\u8bf7\u6c42<\/a>\u00a0\u4e00\u7ae0\u6240\u8ff0\uff0c<\/li>\n<li><strong><code>&quot;same-origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u7981\u6b62\u8de8\u6e90\u8bf7\u6c42\uff0c<\/li>\n<li><strong><code>&quot;no-cors&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u53ea\u5141\u8bb8\u5b89\u5168\u7684\u8de8\u6e90\u8bf7\u6c42\u3002<br \/>\n\u5f53\u00a0<code>fetch<\/code>\u00a0\u7684 URL \u6765\u81ea\u4e8e\u7b2c\u4e09\u65b9\uff0c\u5e76\u4e14\u6211\u4eec\u60f3\u8981\u4e00\u4e2a\u201c\u65ad\u7535\u5f00\u5173\u201d\u6765\u9650\u5236\u8de8\u6e90\u80fd\u529b\u65f6\uff0c\u6b64\u9009\u9879\u53ef\u80fd\u5f88\u6709\u7528\u3002<\/li>\n<\/ul>\n<h2>credentials<\/h2>\n<p><code>credentials<\/code>\u00a0\u9009\u9879\u6307\u5b9a\u00a0<code>fetch<\/code>\u00a0\u662f\u5426\u5e94\u8be5\u968f\u8bf7\u6c42\u53d1\u9001 cookie \u548c HTTP-Authorization header\u3002<\/p>\n<ul>\n<li><strong><code>&quot;same-origin&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u9ed8\u8ba4\u503c\uff0c\u5bf9\u4e8e\u8de8\u6e90\u8bf7\u6c42\u4e0d\u53d1\u9001\uff0c<\/li>\n<li><strong><code>&quot;include&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u603b\u662f\u53d1\u9001\uff0c\u9700\u8981\u6765\u81ea\u8de8\u6e90\u670d\u52a1\u5668\u7684\u00a0<code>Access-Control-Allow-Credentials<\/code>\uff0c\u624d\u80fd\u4f7f JavaScript \u80fd\u591f\u8bbf\u95ee\u54cd\u5e94\uff0c\u8be6\u7ec6\u5185\u5bb9\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">Fetch\uff1a\u8de8\u6e90\u8bf7\u6c42<\/a>\u00a0\u4e00\u7ae0\u6709\u8be6\u7ec6\u4ecb\u7ecd\uff0c<\/li>\n<li><strong><code>&quot;omit&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u4e0d\u53d1\u9001\uff0c\u5373\u4f7f\u5bf9\u4e8e\u540c\u6e90\u8bf7\u6c42\u3002<\/li>\n<\/ul>\n<h2>cache<\/h2>\n<p>\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c<code>fetch<\/code>\u00a0\u8bf7\u6c42\u4f7f\u7528\u6807\u51c6\u7684 HTTP \u7f13\u5b58\u3002\u5c31\u662f\u8bf4\uff0c\u5b83\u9075\u4ece\u00a0<code>Expires<\/code>\uff0c<code>Cache-Control<\/code>\u00a0header\uff0c\u53d1\u9001\u00a0<code>If-Modified-Since<\/code>\uff0c\u7b49\u3002\u5c31\u50cf\u5e38\u89c4\u7684 HTTP \u8bf7\u6c42\u90a3\u6837\u3002<br \/>\n\u4f7f\u7528\u00a0<code>cache<\/code>\u00a0\u9009\u9879\u53ef\u4ee5\u5ffd\u7565 HTTP \u7f13\u5b58\u6216\u8005\u5bf9\u5176\u7528\u6cd5\u8fdb\u884c\u5fae\u8c03\uff1a<\/p>\n<ul>\n<li><strong><code>&quot;default&quot;<\/code><\/strong>\u00a0\u2014\u2014\u00a0<code>fetch<\/code>\u00a0\u4f7f\u7528\u6807\u51c6\u7684 HTTP \u7f13\u5b58\u89c4\u5219\u548c header\uff0c<\/li>\n<li><strong><code>&quot;no-store&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u5b8c\u5168\u5ffd\u7565 HTTP \u7f13\u5b58\uff0c\u5982\u679c\u6211\u4eec\u8bbe\u7f6e header\u00a0<code>If-Modified-Since<\/code>\uff0c<code>If-None-Match<\/code>\uff0c<code>If-Unmodified-Since<\/code>\uff0c<code>If-Match<\/code>\uff0c\u6216\u00a0<code>If-Range<\/code>\uff0c\u5219\u6b64\u6a21\u5f0f\u4f1a\u6210\u4e3a\u9ed8\u8ba4\u6a21\u5f0f\uff0c<\/li>\n<li><strong><code>&quot;reload&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u4e0d\u4ece HTTP \u7f13\u5b58\u4e2d\u83b7\u53d6\u7ed3\u679c\uff08\u5982\u679c\u6709\uff09\uff0c\u800c\u662f\u4f7f\u7528\u54cd\u5e94\u586b\u5145\u7f13\u5b58\uff08\u5982\u679c response header \u5141\u8bb8\u6b64\u64cd\u4f5c\uff09\uff0c<\/li>\n<li><strong><code>&quot;no-cache&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u5982\u679c\u6709\u4e00\u4e2a\u5df2\u7f13\u5b58\u7684\u54cd\u5e94\uff0c\u5219\u521b\u5efa\u4e00\u4e2a\u6709\u6761\u4ef6\u7684\u8bf7\u6c42\uff0c\u5426\u5219\u521b\u5efa\u4e00\u4e2a\u666e\u901a\u7684\u8bf7\u6c42\u3002\u4f7f\u7528\u54cd\u5e94\u586b\u5145 HTTP \u7f13\u5b58\uff0c<\/li>\n<li><strong><code>&quot;force-cache&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u4f7f\u7528\u6765\u81ea HTTP \u7f13\u5b58\u7684\u54cd\u5e94\uff0c\u5373\u4f7f\u8be5\u54cd\u5e94\u5df2\u8fc7\u65f6\uff08stale\uff09\u3002\u5982\u679c HTTP \u7f13\u5b58\u4e2d\u6ca1\u6709\u54cd\u5e94\uff0c\u5219\u521b\u5efa\u4e00\u4e2a\u5e38\u89c4\u7684 HTTP \u8bf7\u6c42\uff0c\u884c\u4e3a\u50cf\u6b63\u5e38\u90a3\u6837\uff0c<\/li>\n<li><strong><code>&quot;only-if-cached&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u4f7f\u7528\u6765\u81ea HTTP \u7f13\u5b58\u7684\u54cd\u5e94\uff0c\u5373\u4f7f\u8be5\u54cd\u5e94\u5df2\u8fc7\u65f6\uff08stale\uff09\u3002\u5982\u679c HTTP \u7f13\u5b58\u4e2d\u6ca1\u6709\u54cd\u5e94\uff0c\u5219\u62a5\u9519\u3002\u53ea\u6709\u5f53\u00a0<code>mode<\/code>\u00a0\u4e3a\u00a0<code>same-origin<\/code>\u00a0\u65f6\u751f\u6548\u3002<\/li>\n<\/ul>\n<h2>redirect<\/h2>\n<p>\u901a\u5e38\u6765\u8bf4\uff0c<code>fetch<\/code>\u00a0\u900f\u660e\u5730\u9075\u5faa HTTP \u91cd\u5b9a\u5411\uff0c\u4f8b\u5982 301\uff0c302 \u7b49\u3002<br \/>\n<code>redirect<\/code>\u00a0\u9009\u9879\u5141\u8bb8\u5bf9\u6b64\u8fdb\u884c\u66f4\u6539\uff1a<\/p>\n<ul>\n<li><strong><code>&quot;follow&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u9ed8\u8ba4\u503c\uff0c\u9075\u5faa HTTP \u91cd\u5b9a\u5411\uff0c<\/li>\n<li><strong><code>&quot;error&quot;<\/code><\/strong>\u00a0\u2014\u2014 HTTP \u91cd\u5b9a\u5411\u65f6\u62a5\u9519\uff0c<\/li>\n<li><strong><code>&quot;manual&quot;<\/code><\/strong>\u00a0\u2014\u2014 \u5141\u8bb8\u624b\u52a8\u5904\u7406 HTTP \u91cd\u5b9a\u5411\u3002\u5728\u91cd\u5b9a\u5411\u7684\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u5c06\u83b7\u5f97\u4e00\u4e2a\u7279\u6b8a\u7684\u54cd\u5e94\u5bf9\u8c61\uff0c\u5176\u4e2d\u5305\u542b\u00a0<code>response.type=&quot;opaqueredirect&quot;<\/code>\u00a0\u548c\u5f52\u96f6\/\u7a7a\u72b6\u6001\u4ee5\u53ca\u5927\u591a\u6570\u5176\u4ed6\u5c5e\u6027\u3002<\/li>\n<\/ul>\n<h2>integrity<\/h2>\n<p><code>integrity<\/code>\u00a0\u9009\u9879\u5141\u8bb8\u68c0\u67e5\u54cd\u5e94\u662f\u5426\u4e0e\u5df2\u77e5\u7684\u9884\u5148\u6821\u9a8c\u548c\u76f8\u5339\u914d\u3002<br \/>\n\u6b63\u5982\u00a0<a href=\"https:\/\/w3c.github.io\/webappsec-subresource-integrity\/\">\u89c4\u8303<\/a>\u00a0\u6240\u63cf\u8ff0\u7684\uff0c\u652f\u6301\u7684\u54c8\u5e0c\u51fd\u6570\u6709 SHA-256\uff0cSHA-384\uff0c\u548c SHA-512\uff0c\u53ef\u80fd\u8fd8\u6709\u5176\u4ed6\u7684\uff0c\u8fd9\u53d6\u51b3\u4e8e\u6d4f\u89c8\u5668\u3002<br \/>\n\u4f8b\u5982\uff0c\u6211\u4eec\u4e0b\u8f7d\u4e00\u4e2a\u6587\u4ef6\uff0c\u5e76\u4e14\u6211\u4eec\u77e5\u9053\u5b83\u7684 SHA-256 \u6821\u9a8c\u548c\u4e3a \u201cabcdef\u201d\uff08\u5f53\u7136\uff0c\u5b9e\u9645\u6821\u9a8c\u548c\u4f1a\u66f4\u957f\uff09\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u5c06\u5176\u653e\u5728\u00a0<code>integrity<\/code>\u00a0\u9009\u9879\u4e2d\uff0c\u5c31\u50cf\u8fd9\u6837:<\/p>\n<pre><code class=\"language-js\">fetch('http:\/\/site.com\/file', {\n  integrity: 'sha256-abcdef'\n});\n<\/code><\/pre>\n<p>\u7136\u540e\u00a0<code>fetch<\/code>\u00a0\u5c06\u81ea\u884c\u8ba1\u7b97 SHA-256 \u5e76\u5c06\u5176\u4e0e\u6211\u4eec\u7684\u5b57\u7b26\u4e32\u8fdb\u884c\u6bd4\u8f83\u3002\u5982\u679c\u4e0d\u5339\u914d\uff0c\u5219\u4f1a\u89e6\u53d1\u9519\u8bef\u3002<\/p>\n<h2>keepalive<\/h2>\n<p><code>keepalive<\/code>\u00a0\u9009\u9879\u8868\u793a\u8be5\u8bf7\u6c42\u53ef\u80fd\u4f1a\u5728\u7f51\u9875\u5173\u95ed\u540e\u7ee7\u7eed\u5b58\u5728\u3002<br \/>\n\u4f8b\u5982\uff0c\u6211\u4eec\u6536\u96c6\u6709\u5173\u5f53\u524d\u8bbf\u95ee\u8005\u662f\u5982\u4f55\u4f7f\u7528\u6211\u4eec\u7684\u9875\u9762\uff08\u9f20\u6807\u70b9\u51fb\uff0c\u4ed6\u67e5\u770b\u7684\u9875\u9762\u7247\u6bb5\uff09\u7684\u7edf\u8ba1\u4fe1\u606f\uff0c\u4ee5\u5206\u6790\u548c\u6539\u5584\u7528\u6237\u4f53\u9a8c\u3002<br \/>\n\u5f53\u8bbf\u95ee\u8005\u79bb\u5f00\u6211\u4eec\u7684\u7f51\u9875\u65f6 \u2014\u2014 \u6211\u4eec\u5e0c\u671b\u80fd\u591f\u5c06\u6570\u636e\u4fdd\u5b58\u5230\u6211\u4eec\u7684\u670d\u52a1\u5668\u4e0a\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>window.onunload<\/code>\u00a0\u4e8b\u4ef6\u6765\u5b9e\u73b0\uff1a<\/p>\n<pre><code class=\"language-js\">window.onunload = function() {\n  fetch('\/analytics', {\n    method: 'POST',\n    body: &quot;statistics&quot;,\n    keepalive: true\n  });\n};\n<\/code><\/pre>\n<p>\u901a\u5e38\uff0c\u5f53\u4e00\u4e2a\u6587\u6863\u88ab\u5378\u8f7d\u65f6\uff08unloaded\uff09\uff0c\u6240\u6709\u76f8\u5173\u7684\u7f51\u7edc\u8bf7\u6c42\u90fd\u4f1a\u88ab\u4e2d\u6b62\u3002\u4f46\u662f\uff0c<code>keepalive<\/code>\u00a0\u9009\u9879\u544a\u8bc9\u6d4f\u89c8\u5668\uff0c\u5373\u4f7f\u5728\u79bb\u5f00\u9875\u9762\u540e\uff0c\u4e5f\u8981\u5728\u540e\u53f0\u6267\u884c\u8bf7\u6c42\u3002\u6240\u4ee5\uff0c\u6b64\u9009\u9879\u5bf9\u4e8e\u6211\u4eec\u7684\u8bf7\u6c42\u6210\u529f\u81f3\u5173\u91cd\u8981\u3002<br \/>\n\u5b83\u6709\u4e00\u4e9b\u9650\u5236\uff1a<\/p>\n<ul>\n<li>\u6211\u4eec\u65e0\u6cd5\u53d1\u9001\u5146\u5b57\u8282\u7684\u6570\u636e\uff1a<code>keepalive<\/code>\u00a0\u8bf7\u6c42\u7684 body \u9650\u5236\u4e3a 64KB\u3002\n<ul>\n<li>\u5982\u679c\u6211\u4eec\u9700\u8981\u6536\u96c6\u6709\u5173\u8bbf\u95ee\u7684\u5927\u91cf\u7edf\u8ba1\u4fe1\u606f\uff0c\u6211\u4eec\u5219\u5e94\u8be5\u5c06\u5176\u5b9a\u671f\u4ee5\u6570\u636e\u5305\u7684\u5f62\u5f0f\u53d1\u9001\u51fa\u53bb\uff0c\u8fd9\u6837\u5c31\u4e0d\u4f1a\u7559\u4e0b\u592a\u591a\u6570\u636e\u7ed9\u6700\u540e\u7684\u00a0<code>onunload<\/code>\u00a0\u8bf7\u6c42\u4e86\u3002<\/li>\n<li>\u6b64\u9650\u5236\u662f\u88ab\u5e94\u7528\u4e8e\u5f53\u524d\u6240\u6709\u00a0<code>keepalive<\/code>\u00a0\u8bf7\u6c42\u7684\u603b\u548c\u7684\u3002\u6362\u53e5\u8bdd\u8bf4\uff0c\u6211\u4eec\u53ef\u4ee5\u5e76\u884c\u6267\u884c\u591a\u4e2a\u00a0<code>keepalive<\/code>\u00a0\u8bf7\u6c42\uff0c\u4f46\u5b83\u4eec\u7684 body \u957f\u5ea6\u4e4b\u548c\u4e0d\u5f97\u8d85\u8fc7 64KB\u3002<\/li>\n<\/ul>\n<\/li>\n<li>\u5982\u679c\u6587\u6863\uff08document\uff09\u5df2\u5378\u8f7d\uff08unloaded\uff09\uff0c\u6211\u4eec\u5c31\u65e0\u6cd5\u5904\u7406\u670d\u52a1\u5668\u54cd\u5e94\u3002\u56e0\u6b64\uff0c\u5728\u6211\u4eec\u7684\u793a\u4f8b\u4e2d\uff0c\u56e0\u4e3a\u00a0<code>keepalive<\/code>\uff0c\u6240\u4ee5\u00a0<code>fetch<\/code>\u00a0\u4f1a\u6210\u529f\uff0c\u4f46\u662f\u540e\u7eed\u7684\u51fd\u6570\u5c06\u65e0\u6cd5\u6b63\u5e38\u5de5\u4f5c\u3002\n<ul>\n<li>\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u4f8b\u5982\u53d1\u9001\u7edf\u8ba1\u4fe1\u606f\uff0c\u8fd9\u4e0d\u662f\u95ee\u9898\uff0c\u56e0\u4e3a\u670d\u52a1\u5668\u53ea\u63a5\u6536\u6570\u636e\uff0c\u5e76\u901a\u5e38\u5411\u6b64\u7c7b\u8bf7\u6c42\u53d1\u9001\u7a7a\u7684\u54cd\u5e94\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h1>URL \u5bf9\u8c61<\/h1>\n<p>\u5185\u5efa\u7684\u00a0<a href=\"https:\/\/url.spec.whatwg.org\/#api\">URL<\/a>\u00a0\u7c7b\u63d0\u4f9b\u4e86\u7528\u4e8e\u521b\u5efa\u548c\u89e3\u6790 URL \u7684\u4fbf\u6377\u63a5\u53e3\u3002<br \/>\n\u6ca1\u6709\u4efb\u4f55\u4e00\u4e2a\u7f51\u7edc\u65b9\u6cd5\u4e00\u5b9a\u9700\u8981\u4f7f\u7528\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\uff0c\u5b57\u7b26\u4e32\u5c31\u8db3\u591f\u4e86\u3002\u6240\u4ee5\u4ece\u6280\u672f\u4e0a\u8bb2\uff0c\u6211\u4eec\u5e76\u4e0d\u662f\u5fc5\u987b\u4f7f\u7528\u00a0<code>URL<\/code>\u3002\u4f46\u662f\u6709\u4e9b\u65f6\u5019\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u771f\u7684\u5f88\u6709\u7528\u3002<\/p>\n<h2>\u521b\u5efa URL \u5bf9\u8c61<\/h2>\n<p>\u521b\u5efa\u4e00\u4e2a\u65b0\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u7684\u8bed\u6cd5\uff1a<\/p>\n<pre><code class=\"language-js\">new URL(url, [base])\n<\/code><\/pre>\n<ul>\n<li><strong><code>url<\/code><\/strong>\u00a0\u2014\u2014 \u5b8c\u6574\u7684 URL\uff0c\u6216\u8005\u4ec5\u8def\u5f84\uff08\u5982\u679c\u8bbe\u7f6e\u4e86 base\uff09\uff0c<\/li>\n<li><strong><code>base<\/code><\/strong>\u00a0\u2014\u2014 \u53ef\u9009\u7684 base URL\uff1a\u5982\u679c\u8bbe\u7f6e\u4e86\u6b64\u53c2\u6570\uff0c\u4e14\u53c2\u6570\u00a0<code>url<\/code>\u00a0\u53ea\u6709\u8def\u5f84\uff0c\u5219\u4f1a\u6839\u636e\u8fd9\u4e2a\u00a0<code>base<\/code>\u00a0\u751f\u6210 URL\u3002<br \/>\n\u4f8b\u5982\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let url = new URL('https:\/\/javascript.info\/profile\/admin');\n<\/code><\/pre>\n<p>\u4e0b\u9762\u8fd9\u4e24\u4e2a URL \u662f\u4e00\u6837\u7684\uff1a<\/p>\n<pre><code class=\"language-js\">let url1 = new URL('https:\/\/javascript.info\/profile\/admin');\nlet url2 = new URL('\/profile\/admin', 'https:\/\/javascript.info');\n\nalert(url1); \/\/ https:\/\/javascript.info\/profile\/admin\nalert(url2); \/\/ https:\/\/javascript.info\/profile\/admin\n<\/code><\/pre>\n<p>\u6211\u4eec\u53ef\u4ee5\u6839\u636e\u76f8\u5bf9\u4e8e\u73b0\u6709 URL \u7684\u8def\u5f84\u8f7b\u677e\u521b\u5efa\u4e00\u4e2a\u65b0\u7684 URL\uff1a<\/p>\n<pre><code class=\"language-js\">let url = new URL('https:\/\/javascript.info\/profile\/admin');\nlet newUrl = new URL('tester', url);\n\nalert(newUrl); \/\/ https:\/\/javascript.info\/profile\/tester\n<\/code><\/pre>\n<p><code>URL<\/code>\u00a0\u5bf9\u8c61\u7acb\u5373\u5141\u8bb8\u6211\u4eec\u8bbf\u95ee\u5176\u7ec4\u4ef6\uff0c\u56e0\u6b64\u8fd9\u662f\u4e00\u4e2a\u89e3\u6790 url \u7684\u597d\u65b9\u6cd5\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">let url = new URL('https:\/\/javascript.info\/url');\n\nalert(url.protocol); \/\/ https:\nalert(url.host);     \/\/ javascript.info\nalert(url.pathname); \/\/ \/url\n<\/code><\/pre>\n<p>\u8fd9\u662f URL \u7ec4\u4ef6\u7684\u5907\u5fd8\u5355\uff1a<br \/>\n<img decoding=\"async\" src=\"https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240701115002-4.png\" alt=\"Pasted image 20240701115002.png\"><\/p>\n<ul>\n<li><code>href<\/code>\u00a0\u662f\u5b8c\u6574\u7684 URL\uff0c\u4e0e\u00a0<code>url.toString()<\/code>\u00a0\u76f8\u540c<\/li>\n<li><code>protocol<\/code>\u00a0\u4ee5\u5192\u53f7\u5b57\u7b26\u00a0<code>:<\/code>\u00a0\u7ed3\u5c3e<\/li>\n<li><code>search<\/code>\u00a0\u2014\u2014 \u4ee5\u95ee\u53f7\u00a0<code>?<\/code>\u00a0\u5f00\u5934\u7684\u4e00\u4e32\u53c2\u6570<\/li>\n<li><code>hash<\/code>\u00a0\u4ee5\u54c8\u5e0c\u5b57\u7b26\u00a0<code>#<\/code>\u00a0\u5f00\u5934<\/li>\n<li>\u5982\u679c\u5b58\u5728 HTTP \u8eab\u4efd\u9a8c\u8bc1\uff0c\u5219\u8fd9\u91cc\u53ef\u80fd\u8fd8\u4f1a\u6709\u00a0<code>user<\/code>\u00a0\u548c\u00a0<code>password<\/code>\u00a0\u5c5e\u6027\uff1a<code>http:\/\/login:password@site.com<\/code>\uff08\u56fe\u7247\u4e0a\u6ca1\u6709\uff0c\u5f88\u5c11\u88ab\u7528\u5230\uff09\u3002<\/li>\n<\/ul>\n<blockquote>\n<p>\u6211\u4eec\u53ef\u4ee5\u5c06\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u4f20\u9012\u7ed9\u7f51\u7edc\uff08\u548c\u5927\u591a\u6570\u5176\u4ed6\uff09\u65b9\u6cd5\uff0c\u800c\u4e0d\u662f\u5b57\u7b26\u4e32<br \/>\n\u6211\u4eec\u53ef\u4ee5\u5728\u00a0<code>fetch<\/code>\u00a0\u6216\u00a0<code>XMLHttpRequest<\/code>\u00a0\u4e2d\u4f7f\u7528\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\uff0c\u51e0\u4e4e\u53ef\u4ee5\u5728\u4efb\u4f55\u9700\u8981 URL \u5b57\u7b26\u4e32\u7684\u5730\u65b9\u90fd\u80fd\u4f7f\u7528\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u3002<br \/>\n\u901a\u5e38\uff0c<code>URL<\/code>\u00a0\u5bf9\u8c61\u53ef\u4ee5\u66ff\u4ee3\u5b57\u7b26\u4e32\u4f20\u9012\u7ed9\u4efb\u4f55\u65b9\u6cd5\uff0c\u56e0\u4e3a\u5927\u591a\u6570\u65b9\u6cd5\u90fd\u4f1a\u6267\u884c\u5b57\u7b26\u4e32\u8f6c\u6362\uff0c\u8fd9\u4f1a\u5c06\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u8f6c\u6362\u4e3a\u5177\u6709\u5b8c\u6574 URL \u7684\u5b57\u7b26\u4e32\u3002<\/p>\n<\/blockquote>\n<h2>SearchParams &quot;?...&quot;<\/h2>\n<p>\u5047\u8bbe\uff0c\u6211\u4eec\u60f3\u8981\u521b\u5efa\u4e00\u4e2a\u5177\u6709\u7ed9\u5b9a\u641c\u7d22\u53c2\u6570\u7684 url\uff0c\u4f8b\u5982\uff1a<code>https:\/\/google.com\/search?query=JavaScript<\/code>\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u5728 URL \u5b57\u7b26\u4e32\u4e2d\u63d0\u4f9b\u5b83\u4eec\uff1a<\/p>\n<pre><code class=\"language-js\">new URL('https:\/\/google.com\/search?query=JavaScript')\n<\/code><\/pre>\n<p>\u2026\u2026\u4f46\u662f\uff0c\u5982\u679c\u53c2\u6570\u4e2d\u5305\u542b\u7a7a\u683c\uff0c\u975e\u62c9\u4e01\u5b57\u6bcd\u7b49\uff08\u5177\u4f53\u53c2\u89c1\u4e0b\u6587\uff09\uff0c\u53c2\u6570\u5c31\u9700\u8981\u88ab\u7f16\u7801\u3002<br \/>\n\u56e0\u6b64\uff0c\u6709\u4e00\u4e2a URL \u5c5e\u6027\u7528\u4e8e\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff1a<code>url.searchParams<\/code>\uff0c<a href=\"https:\/\/url.spec.whatwg.org\/#urlsearchparams\">URLSearchParams<\/a>\u00a0\u7c7b\u578b\u7684\u5bf9\u8c61\u3002<br \/>\n\u5b83\u4e3a\u641c\u7d22\u53c2\u6570\u63d0\u4f9b\u4e86\u7b80\u4fbf\u7684\u65b9\u6cd5\uff1a<\/p>\n<ul>\n<li><strong><code>append(name, value)<\/code><\/strong>\u00a0\u2014\u2014 \u6309\u7167\u00a0<code>name<\/code>\u00a0\u6dfb\u52a0\u53c2\u6570\uff0c<\/li>\n<li><strong><code>delete(name)<\/code><\/strong>\u00a0\u2014\u2014 \u6309\u7167\u00a0<code>name<\/code>\u00a0\u79fb\u9664\u53c2\u6570\uff0c<\/li>\n<li><strong><code>get(name)<\/code><\/strong>\u00a0\u2014\u2014 \u6309\u7167\u00a0<code>name<\/code>\u00a0\u83b7\u53d6\u53c2\u6570\uff0c<\/li>\n<li><strong><code>getAll(name)<\/code><\/strong>\u00a0\u2014\u2014 \u83b7\u53d6\u76f8\u540c\u00a0<code>name<\/code>\u00a0\u7684\u6240\u6709\u53c2\u6570\uff08\u8fd9\u662f\u53ef\u884c\u7684\uff0c\u4f8b\u5982\u00a0<code>?user=John&amp;user=Pete<\/code>\uff09\uff0c<\/li>\n<li><strong><code>has(name)<\/code><\/strong>\u00a0\u2014\u2014 \u6309\u7167\u00a0<code>name<\/code>\u00a0\u68c0\u67e5\u53c2\u6570\u662f\u5426\u5b58\u5728\uff0c<\/li>\n<li><strong><code>set(name, value)<\/code><\/strong>\u00a0\u2014\u2014 set\/replace \u53c2\u6570\uff0c<\/li>\n<li><strong><code>sort()<\/code><\/strong>\u00a0\u2014\u2014 \u6309 name \u5bf9\u53c2\u6570\u8fdb\u884c\u6392\u5e8f\uff0c\u5f88\u5c11\u4f7f\u7528\uff0c<\/li>\n<li>\u2026\u2026\u5e76\u4e14\u5b83\u662f\u53ef\u8fed\u4ee3\u7684\uff0c\u7c7b\u4f3c\u4e8e\u00a0<code>Map<\/code>\u3002<br \/>\n\u5305\u542b\u7a7a\u683c\u548c\u6807\u70b9\u7b26\u53f7\u7684\u53c2\u6570\u7684\u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let url = new URL('https:\/\/google.com\/search');\n\nurl.searchParams.set('q', 'test me!'); \/\/ \u6dfb\u52a0\u5e26\u6709\u4e00\u4e2a\u7a7a\u683c\u548c\u4e00\u4e2a ! \u7684\u53c2\u6570\n\nalert(url); \/\/ https:\/\/google.com\/search?q=test+me%21\n\nurl.searchParams.set('tbs', 'qdr:y'); \/\/ \u6dfb\u52a0\u5e26\u6709\u4e00\u4e2a\u5192\u53f7 : \u7684\u53c2\u6570\n\n\/\/ \u53c2\u6570\u4f1a\u88ab\u81ea\u52a8\u7f16\u7801\nalert(url); \/\/ https:\/\/google.com\/search?q=test+me%21&amp;tbs=qdr%3Ay\n\n\/\/ \u904d\u5386\u641c\u7d22\u53c2\u6570\uff08\u88ab\u89e3\u7801\uff09\nfor(let [name, value] of url.searchParams) {\n  alert(`${name}=${value}`); \/\/ q=test me!\uff0c\u7136\u540e\u662f tbs=qdr:y\n}\n<\/code><\/pre>\n<h2>\u7f16\u7801 encoding<\/h2>\n<p><a href=\"https:\/\/tools.ietf.org\/html\/rfc3986\">RFC3986<\/a>\u00a0\u6807\u51c6\u5b9a\u4e49\u4e86 URL \u4e2d\u5141\u8bb8\u54ea\u4e9b\u5b57\u7b26\uff0c\u4e0d\u5141\u8bb8\u54ea\u4e9b\u5b57\u7b26\u3002<br \/>\n\u90a3\u4e9b\u4e0d\u88ab\u5141\u8bb8\u7684\u5b57\u7b26\u5fc5\u987b\u88ab\u7f16\u7801\uff0c\u4f8b\u5982\u975e\u62c9\u4e01\u5b57\u6bcd\u548c\u7a7a\u683c \u2014\u2014 \u7528\u5176 UTF-8 \u4ee3\u7801\u4ee3\u66ff\uff0c\u524d\u7f00\u4e3a\u00a0<code>%<\/code>\uff0c\u4f8b\u5982\u00a0<code>%20<\/code>\uff08\u7531\u4e8e\u5386\u53f2\u539f\u56e0\uff0c\u7a7a\u683c\u53ef\u4ee5\u7528\u00a0<code>+<\/code>\u00a0\u7f16\u7801\uff0c\u4f46\u8fd9\u662f\u4e00\u4e2a\u4f8b\u5916\uff09\u3002<br \/>\n\u597d\u6d88\u606f\u662f\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u4f1a\u81ea\u52a8\u5904\u7406\u8fd9\u4e9b\u3002\u6211\u4eec\u4ec5\u9700\u63d0\u4f9b\u672a\u7f16\u7801\u7684\u53c2\u6570\uff0c\u7136\u540e\u5c06\u00a0<code>URL<\/code>\u00a0\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \u5728\u6b64\u793a\u4f8b\u4e2d\u4f7f\u7528\u4e00\u4e9b\u897f\u91cc\u5c14\u5b57\u7b26\n\nlet url = new URL('https:\/\/ru.wikipedia.org\/wiki\/\u0422\u0435\u0441\u0442');\n\nurl.searchParams.set('key', '\u044a');\nalert(url); \/\/https:\/\/ru.wikipedia.org\/wiki\/%D0%A2%D0%B5%D1%81%D1%82?key=%D1%8A\n<\/code><\/pre>\n<p>\u6b63\u5982\u4f60\u6240\u770b\u5230\u7684\uff0curl \u8def\u5f84\u4e2d\u7684\u00a0<code>\u0422\u0435\u0441\u0442<\/code>\u00a0\u548c\u00a0<code>\u044a<\/code>\u00a0\u53c2\u6570\u90fd\u88ab\u7f16\u7801\u4e86\u3002<br \/>\nURL \u53d8\u957f\u4e86\uff0c\u56e0\u4e3a\u6bcf\u4e2a\u897f\u91cc\u5c14\u5b57\u6bcd\u7528 UTF-8 \u7f16\u7801\u7684\u4e24\u4e2a\u5b57\u8282\u8868\u793a\uff0c\u56e0\u6b64\u8fd9\u91cc\u6709\u4e24\u4e2a\u00a0<code>%..<\/code>\u00a0\u5b9e\u4f53\uff08entities\uff09\u3002<\/p>\n<h3>\u7f16\u7801\u5b57\u7b26\u4e32<\/h3>\n<p>\u5728\u8fc7\u53bb\uff0c\u5728\u51fa\u73b0\u00a0<code>URL<\/code>\u00a0\u5bf9\u8c61\u4e4b\u524d\uff0c\u4eba\u4eec\u4f7f\u7528\u5b57\u7b26\u4e32\u4f5c\u4e3a URL\u3002<br \/>\n\u800c\u73b0\u5728\uff0c<code>URL<\/code>\u00a0\u5bf9\u8c61\u901a\u5e38\u66f4\u65b9\u4fbf\uff0c\u4f46\u662f\u4ecd\u7136\u53ef\u4ee5\u4f7f\u7528\u5b57\u7b26\u4e32\u3002\u5728\u5f88\u591a\u60c5\u51b5\u4e0b\uff0c\u4f7f\u7528\u5b57\u7b26\u4e32\u53ef\u4ee5\u4f7f\u4ee3\u7801\u66f4\u77ed\u3002<br \/>\n\u5982\u679c\u4f7f\u7528\u5b57\u7b26\u4e32\uff0c\u5219\u9700\u8981\u624b\u52a8\u7f16\u7801\/\u89e3\u7801\u7279\u6b8a\u5b57\u7b26\u3002<br \/>\n\u4e0b\u9762\u662f\u7528\u4e8e\u7f16\u7801\/\u89e3\u7801 URL \u7684\u5185\u5efa\u51fd\u6570\uff1a<\/p>\n<ul>\n<li><a href=\"https:\/\/developer.mozilla.org\/zh\/docs\/Web\/JavaScript\/Reference\/Global_Objects\/encodeURI\">encodeURI<\/a>\u00a0\u2014\u2014 \u7f16\u7801\u6574\u4e2a URL\u3002<\/li>\n<li><a href=\"https:\/\/developer.mozilla.org\/zh\/docs\/Web\/JavaScript\/Reference\/Global_Objects\/decodeURI\">decodeURI<\/a>\u00a0\u2014\u2014 \u89e3\u7801\u4e3a\u7f16\u7801\u524d\u7684\u72b6\u6001\u3002<\/li>\n<li><a href=\"https:\/\/developer.mozilla.org\/zh\/docs\/Web\/JavaScript\/Reference\/Global_Objects\/encodeURIComponent\">encodeURIComponent<\/a>\u00a0\u2014\u2014 \u7f16\u7801 URL \u7ec4\u4ef6\uff0c\u4f8b\u5982\u641c\u7d22\u53c2\u6570\uff0c\u6216\u8005 hash\uff0c\u6216\u8005 pathname\u3002<\/li>\n<li><a href=\"https:\/\/developer.mozilla.org\/zh\/docs\/Web\/JavaScript\/Reference\/Global_Objects\/decodeURIComponent\">decodeURIComponent<\/a>\u00a0\u2014\u2014 \u89e3\u7801\u4e3a\u7f16\u7801\u524d\u7684\u72b6\u6001\u3002<br \/>\n\u4e00\u4e2a\u81ea\u7136\u7684\u95ee\u9898\uff1a\u201c<code>encodeURIComponent<\/code>\u00a0\u548c\u00a0<code>encodeURI<\/code>\u00a0\u4e4b\u95f4\u6709\u4ec0\u4e48\u533a\u522b\uff1f\u6211\u4eec\u4ec0\u4e48\u65f6\u5019\u5e94\u8be5\u4f7f\u7528\u54ea\u4e2a\uff1f\u201d<br \/>\n\u5982\u679c\u6211\u4eec\u770b\u4e00\u4e2a URL\uff0c\u5c31\u5bb9\u6613\u7406\u89e3\u4e86\uff0c\u5b83\u88ab\u5206\u89e3\u4e3a\u672c\u6587\u4e0a\u9762\u56fe\u4e2d\u6240\u793a\u7684\u7ec4\u4ef6\u5f62\u5f0f\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">https:\/\/site.com:8080\/path\/page?p1=v1&amp;p2=v2#hash\n<\/code><\/pre>\n<p>\u6b63\u5982\u6211\u4eec\u6240\u770b\u5230\u7684\uff0c\u5728 URL \u4e2d\u00a0<code>:<\/code>\uff0c<code>?<\/code>\uff0c<code>=<\/code>\uff0c<code>&amp;<\/code>\uff0c<code>#<\/code>\u00a0\u8fd9\u7c7b\u5b57\u7b26\u662f\u88ab\u5141\u8bb8\u7684\u3002<br \/>\n\u2026\u2026\u53e6\u4e00\u65b9\u9762\uff0c\u5bf9\u4e8e URL \u7684\u5355\u4e2a\u7ec4\u4ef6\uff0c\u4f8b\u5982\u4e00\u4e2a\u641c\u7d22\u53c2\u6570\uff0c\u5219\u5fc5\u987b\u5bf9\u8fd9\u4e9b\u5b57\u7b26\u8fdb\u884c\u7f16\u7801\uff0c\u4ee5\u514d\u7834\u574f URL \u7684\u683c\u5f0f\u3002<\/p>\n<ul>\n<li><code>encodeURI<\/code>\u00a0\u4ec5\u7f16\u7801 URL \u4e2d\u5b8c\u5168\u7981\u6b62\u7684\u5b57\u7b26\u3002<\/li>\n<li><code>encodeURIComponent<\/code>\u00a0\u4e5f\u7f16\u7801\u8fd9\u7c7b\u5b57\u7b26\uff0c\u6b64\u5916\uff0c\u8fd8\u7f16\u7801\u00a0<code>#<\/code>\uff0c<code>$<\/code>\uff0c<code>&amp;<\/code>\uff0c<code>+<\/code>\uff0c<code>,<\/code>\uff0c<code>\/<\/code>\uff0c<code>:<\/code>\uff0c<code>;<\/code>\uff0c<code>=<\/code>\uff0c<code>?<\/code>\u00a0\u548c\u00a0<code>@<\/code>\u00a0\u5b57\u7b26\u3002<br \/>\n\u6240\u4ee5\uff0c\u5bf9\u4e8e\u4e00\u4e2a URL \u6574\u4f53\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>encodeURI<\/code>\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">\/\/ \u5728 url \u8def\u5f84\u4e2d\u4f7f\u7528\u897f\u91cc\u5c14\u5b57\u7b26\nlet url = encodeURI('http:\/\/site.com\/\u043f\u0440\u0438\u0432\u0435\u0442');\n\nalert(url); \/\/ http:\/\/site.com\/%D0%BF%D1%80%D0%B8%D0%B2%D0%B5%D1%82\n<\/code><\/pre>\n<p>\u2026\u2026\u800c\u5bf9\u4e8e URL \u53c2\u6570\uff0c\u6211\u4eec\u5e94\u8be5\u6539\u7528\u00a0<code>encodeURIComponent<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">let music = encodeURIComponent('Rock&amp;Roll');\n\nlet url = `https:\/\/google.com\/search?q=${music}`;\nalert(url); \/\/ https:\/\/google.com\/search?q=Rock%26Roll\n<\/code><\/pre>\n<p>\u5c06\u5176\u4e0e\u00a0<code>encodeURI<\/code>\u00a0\u8fdb\u884c\u6bd4\u8f83\uff1a<\/p>\n<pre><code class=\"language-js\">let music = encodeURI('Rock&amp;Roll');\n\nlet url = `https:\/\/google.com\/search?q=${music}`;\nalert(url); \/\/ https:\/\/google.com\/search?q=Rock&amp;Roll\n<\/code><\/pre>\n<p>\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c<code>encodeURI<\/code>\u00a0\u6ca1\u6709\u5bf9\u00a0<code>&amp;<\/code>\u00a0\u8fdb\u884c\u7f16\u7801\uff0c\u56e0\u4e3a\u5b83\u5bf9\u4e8e\u6574\u4e2a URL \u6765\u8bf4\u662f\u5408\u6cd5\u7684\u5b57\u7b26\u3002<br \/>\n\u4f46\u662f\uff0c\u6211\u4eec\u5e94\u8be5\u7f16\u7801\u5728\u641c\u7d22\u53c2\u6570\u4e2d\u7684\u00a0<code>&amp;<\/code>\u00a0\u5b57\u7b26\uff0c\u5426\u5219\uff0c\u6211\u4eec\u5c06\u5f97\u5230\u00a0<code>q=Rock&amp;Roll<\/code>\u00a0\u2014\u2014 \u5b9e\u9645\u4e0a\u662f\u00a0<code>q=Rock<\/code>\u00a0\u52a0\u4e0a\u67d0\u4e2a\u6666\u6da9\u7684\u53c2\u6570\u00a0<code>Roll<\/code>\u3002\u4e0d\u7b26\u5408\u9884\u671f\u3002<br \/>\n\u56e0\u6b64\uff0c\u5bf9\u4e8e\u6bcf\u4e2a\u641c\u7d22\u53c2\u6570\uff0c\u6211\u4eec\u5e94\u8be5\u4f7f\u7528\u00a0<code>encodeURIComponent<\/code>\uff0c\u4ee5\u5c06\u5176\u6b63\u786e\u5730\u63d2\u5165\u5230 URL \u5b57\u7b26\u4e32\u4e2d\u3002\u6700\u5b89\u5168\u7684\u65b9\u5f0f\u662f\u5bf9 name \u548c value \u90fd\u8fdb\u884c\u7f16\u7801\uff0c\u9664\u975e\u6211\u4eec\u80fd\u591f\u7edd\u5bf9\u786e\u4fdd\u5b83\u53ea\u5305\u542b\u5141\u8bb8\u7684\u5b57\u7b26\u3002<\/p>\n<blockquote>\n<p><code>encode*<\/code>\u00a0\u4e0e\u00a0<code>URL<\/code>\u00a0\u4e4b\u95f4\u7684\u7f16\u7801\u5dee\u5f02<br \/>\n<a href=\"https:\/\/url.spec.whatwg.org\/#url-class\">URL<\/a>\u00a0\u548c\u00a0<a href=\"https:\/\/url.spec.whatwg.org\/#interface-urlsearchparams\">URLSearchParams<\/a>\u00a0\u57fa\u4e8e\u6700\u65b0\u7684 URL \u89c4\u8303\uff1a<a href=\"https:\/\/tools.ietf.org\/html\/rfc3986\">RFC3986<\/a>\uff0c\u800c\u00a0<code>encode*<\/code>\u00a0\u51fd\u6570\u662f\u57fa\u4e8e\u8fc7\u65f6\u7684\u00a0<a href=\"https:\/\/www.ietf.org\/rfc\/rfc2396.txt\">RFC2396<\/a>\u3002<br \/>\n\u5b83\u4eec\u4e4b\u95f4\u6709\u4e00\u4e9b\u533a\u522b\uff0c\u4f8b\u5982\u5bf9 IPv6 \u5730\u5740\u7684\u7f16\u7801\u65b9\u5f0f\u4e0d\u540c\uff1a<\/p>\n<\/blockquote>\n<pre><code class=\"language-js\">\/\/ IPv6 \u5730\u5740\u7684\u5408\u6cd5 url\nlet url = 'http:\/\/[2607:f8b0:4005:802::1007]\/';\n\nalert(encodeURI(url)); \/\/ http:\/\/%5B2607:f8b0:4005:802::1007%5D\/\nalert(new URL(url)); \/\/ http:\/\/[2607:f8b0:4005:802::1007]\/\n<\/code><\/pre>\n<blockquote>\n<p>\u6b63\u5982\u6211\u4eec\u6240\u770b\u5230\u7684\uff0c<code>encodeURI<\/code>\u00a0\u66ff\u6362\u4e86\u65b9\u62ec\u53f7\u00a0<code>[...]<\/code>\uff0c\u8fd9\u662f\u4e0d\u6b63\u786e\u7684\uff0c\u539f\u56e0\u662f\uff1a\u5728 RFC2396 (August 1998) \u65f6\u4ee3\uff0c\u8fd8\u4e0d\u5b58\u5728 IPv6 url\u3002<br \/>\n\u8fd9\u79cd\u60c5\u51b5\u5f88\u5c11\u89c1\uff0c<code>encode*<\/code>\u00a0\u51fd\u6570\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\u90fd\u80fd\u6b63\u5e38\u5de5\u4f5c\u3002<\/p>\n<\/blockquote>\n<h1>XMLHttpRequest<\/h1>\n<p><code>XMLHttpRequest<\/code>\u00a0\u662f\u4e00\u4e2a\u5185\u5efa\u7684\u6d4f\u89c8\u5668\u5bf9\u8c61\uff0c\u5b83\u5141\u8bb8\u4f7f\u7528 JavaScript \u53d1\u9001 HTTP \u8bf7\u6c42\u3002<br \/>\n\u867d\u7136\u5b83\u7684\u540d\u5b57\u91cc\u9762\u6709 \u201cXML\u201d \u4e00\u8bcd\uff0c\u4f46\u5b83\u53ef\u4ee5\u64cd\u4f5c\u4efb\u4f55\u6570\u636e\uff0c\u800c\u4e0d\u4ec5\u4ec5\u662f XML \u683c\u5f0f\u3002\u6211\u4eec\u53ef\u4ee5\u7528\u5b83\u6765\u4e0a\u4f20\/\u4e0b\u8f7d\u6587\u4ef6\uff0c\u8ddf\u8e2a\u8fdb\u5ea6\u7b49\u3002<br \/>\n\u73b0\u5982\u4eca\uff0c\u6211\u4eec\u6709\u4e00\u4e2a\u66f4\u4e3a\u73b0\u4ee3\u7684\u65b9\u6cd5\u53eb\u505a\u00a0<code>fetch<\/code>\uff0c\u5b83\u7684\u51fa\u73b0\u4f7f\u5f97\u00a0<code>XMLHttpRequest<\/code>\u00a0\u5728\u67d0\u79cd\u7a0b\u5ea6\u4e0a\u88ab\u5f03\u7528\u3002<br \/>\n\u5728\u73b0\u4ee3 Web \u5f00\u53d1\u4e2d\uff0c\u51fa\u4e8e\u4ee5\u4e0b\u4e09\u79cd\u539f\u56e0\uff0c\u6211\u4eec\u8fd8\u5728\u4f7f\u7528\u00a0<code>XMLHttpRequest<\/code>\uff1a<\/p>\n<ol>\n<li>\u5386\u53f2\u539f\u56e0\uff1a\u6211\u4eec\u9700\u8981\u652f\u6301\u73b0\u6709\u7684\u4f7f\u7528\u4e86\u00a0<code>XMLHttpRequest<\/code>\u00a0\u7684\u811a\u672c\u3002<\/li>\n<li>\u6211\u4eec\u9700\u8981\u517c\u5bb9\u65e7\u6d4f\u89c8\u5668\uff0c\u5e76\u4e14\u4e0d\u60f3\u7528 polyfill\uff08\u4f8b\u5982\u4e3a\u4e86\u4f7f\u811a\u672c\u66f4\u5c0f\uff09\u3002<\/li>\n<li>\u6211\u4eec\u9700\u8981\u505a\u4e00\u4e9b\u00a0<code>fetch<\/code>\u00a0\u76ee\u524d\u65e0\u6cd5\u505a\u5230\u7684\u4e8b\u60c5\uff0c\u4f8b\u5982\u8ddf\u8e2a\u4e0a\u4f20\u8fdb\u5ea6\u3002<br \/>\n\u8fd9\u4e9b\u8bdd\u542c\u8d77\u6765\u719f\u6089\u5417\uff1f\u5982\u679c\u662f\uff0c\u90a3\u4e48\u8bf7\u7ee7\u7eed\u9605\u8bfb\u4e0b\u9762\u7684\u00a0<code>XMLHttpRequest<\/code>\u00a0\u76f8\u5173\u5185\u5bb9\u5427\u3002\u5982\u679c\u8fd8\u4e0d\u662f\u5f88\u719f\u6089\u7684\u8bdd\uff0c\u90a3\u4e48\u8bf7\u5148\u9605\u8bfb\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch\">Fetch<\/a>\u00a0\u4e00\u7ae0\u7684\u5185\u5bb9\u3002<\/li>\n<\/ol>\n<h2>XMLHttpRequest \u57fa\u7840<\/h2>\n<p>XMLHttpRequest \u6709\u4e24\u79cd\u6267\u884c\u6a21\u5f0f\uff1a\u540c\u6b65\uff08synchronous\uff09\u548c\u5f02\u6b65\uff08asynchronous\uff09\u3002<br \/>\n\u6211\u4eec\u9996\u5148\u6765\u770b\u770b\u6700\u5e38\u7528\u7684\u5f02\u6b65\u6a21\u5f0f\uff1a<br \/>\n\u8981\u53d1\u9001\u8bf7\u6c42\uff0c\u9700\u8981 3 \u4e2a\u6b65\u9aa4\uff1a<\/p>\n<ol>\n<li>\u521b\u5efa\u00a0<code>XMLHttpRequest<\/code>\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">let xhr = new XMLHttpRequest();\n<\/code><\/pre>\n<p>\u6b64\u6784\u9020\u5668\u6ca1\u6709\u53c2\u6570\u3002<br \/>\n2. \u521d\u59cb\u5316\u5b83\uff0c\u901a\u5e38\u5c31\u5728\u00a0<code>new XMLHttpRequest<\/code>\u00a0\u4e4b\u540e\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.open(method, URL, [async, user, password])\n<\/code><\/pre>\n<p>\u6b64\u65b9\u6cd5\u6307\u5b9a\u8bf7\u6c42\u7684\u4e3b\u8981\u53c2\u6570\uff1a<br \/>\n- <code>method<\/code>\u00a0\u2014\u2014 HTTP \u65b9\u6cd5\u3002\u901a\u5e38\u662f\u00a0<code>&quot;GET&quot;<\/code>\u00a0\u6216\u00a0<code>&quot;POST&quot;<\/code>\u3002<br \/>\n- <code>URL<\/code>\u00a0\u2014\u2014 \u8981\u8bf7\u6c42\u7684 URL\uff0c\u901a\u5e38\u662f\u4e00\u4e2a\u5b57\u7b26\u4e32\uff0c\u4e5f\u53ef\u4ee5\u662f\u00a0<a href=\"https:\/\/zh.javascript.info\/url\">URL<\/a>\u00a0\u5bf9\u8c61\u3002<br \/>\n- <code>async<\/code>\u00a0\u2014\u2014 \u5982\u679c\u663e\u5f0f\u5730\u8bbe\u7f6e\u4e3a\u00a0<code>false<\/code>\uff0c\u90a3\u4e48\u8bf7\u6c42\u5c06\u4f1a\u4ee5\u540c\u6b65\u7684\u65b9\u5f0f\u5904\u7406\uff0c\u6211\u4eec\u7a0d\u540e\u4f1a\u8bb2\u5230\u5b83\u3002<br \/>\n- <code>user<\/code>\uff0c<code>password<\/code>\u00a0\u2014\u2014 HTTP \u57fa\u672c\u8eab\u4efd\u9a8c\u8bc1\uff08\u5982\u679c\u9700\u8981\u7684\u8bdd\uff09\u7684\u767b\u5f55\u540d\u548c\u5bc6\u7801\u3002<br \/>\n\u8bf7\u6ce8\u610f\uff0c<code>open<\/code>\u00a0\u8c03\u7528\u4e0e\u5176\u540d\u79f0\u76f8\u53cd\uff0c\u4e0d\u4f1a\u5efa\u7acb\u8fde\u63a5\u3002\u5b83\u4ec5\u914d\u7f6e\u8bf7\u6c42\uff0c\u800c\u7f51\u7edc\u6d3b\u52a8\u4ec5\u4ee5\u00a0<code>send<\/code>\u00a0\u8c03\u7528\u5f00\u542f\u3002<br \/>\n3. \u53d1\u9001\u8bf7\u6c42\u3002<\/p>\n<pre><code class=\"language-js\">xhr.send([body])\n<\/code><\/pre>\n<p>\u8fd9\u4e2a\u65b9\u6cd5\u4f1a\u5efa\u7acb\u8fde\u63a5\uff0c\u5e76\u5c06\u8bf7\u6c42\u53d1\u9001\u5230\u670d\u52a1\u5668\u3002\u53ef\u9009\u53c2\u6570\u00a0<code>body<\/code>\u00a0\u5305\u542b\u4e86 request body\u3002<br \/>\n\u4e00\u4e9b\u8bf7\u6c42\u65b9\u6cd5\uff0c\u50cf\u00a0<code>GET<\/code>\u00a0\u6ca1\u6709 request body\u3002\u8fd8\u6709\u4e00\u4e9b\u8bf7\u6c42\u65b9\u6cd5\uff0c\u50cf\u00a0<code>POST<\/code>\u00a0\u4f7f\u7528\u00a0<code>body<\/code>\u00a0\u5c06\u6570\u636e\u53d1\u9001\u5230\u670d\u52a1\u5668\u3002\u6211\u4eec\u7a0d\u540e\u4f1a\u770b\u5230\u76f8\u5e94\u793a\u4f8b\u3002<br \/>\n4. \u76d1\u542c\u00a0<code>xhr<\/code>\u00a0\u4e8b\u4ef6\u4ee5\u83b7\u53d6\u54cd\u5e94\u3002<br \/>\n\u8fd9\u4e09\u4e2a\u4e8b\u4ef6\u662f\u6700\u5e38\u7528\u7684\uff1a<br \/>\n- <code>load<\/code>\u00a0\u2014\u2014 \u5f53\u8bf7\u6c42\u5b8c\u6210\uff08\u5373\u4f7f HTTP \u72b6\u6001\u4e3a 400 \u6216 500 \u7b49\uff09\uff0c\u5e76\u4e14\u54cd\u5e94\u5df2\u5b8c\u5168\u4e0b\u8f7d\u3002<br \/>\n- <code>error<\/code>\u00a0\u2014\u2014 \u5f53\u65e0\u6cd5\u53d1\u51fa\u8bf7\u6c42\uff0c\u4f8b\u5982\u7f51\u7edc\u4e2d\u65ad\u6216\u8005\u65e0\u6548\u7684 URL\u3002<br \/>\n- <code>progress<\/code>\u00a0\u2014\u2014 \u5728\u4e0b\u8f7d\u54cd\u5e94\u671f\u95f4\u5b9a\u671f\u89e6\u53d1\uff0c\u62a5\u544a\u5df2\u7ecf\u4e0b\u8f7d\u4e86\u591a\u5c11\u3002<\/p>\n<pre><code class=\"language-js\">xhr.onload = function() {\n  alert(`Loaded: ${xhr.status} ${xhr.response}`);\n};\n\nxhr.onerror = function() { \/\/ \u4ec5\u5728\u6839\u672c\u65e0\u6cd5\u53d1\u51fa\u8bf7\u6c42\u65f6\u89e6\u53d1\n  alert(`Network Error`);\n};\n\nxhr.onprogress = function(event) { \/\/ \u5b9a\u671f\u89e6\u53d1\n  \/\/ event.loaded \u2014\u2014 \u5df2\u7ecf\u4e0b\u8f7d\u4e86\u591a\u5c11\u5b57\u8282\n  \/\/ event.lengthComputable = true\uff0c\u5f53\u670d\u52a1\u5668\u53d1\u9001\u4e86 Content-Length header \u65f6\n  \/\/ event.total \u2014\u2014 \u603b\u5b57\u8282\u6570\uff08\u5982\u679c lengthComputable \u4e3a true\uff09\n  alert(`Received ${event.loaded} of ${event.total}`);\n};\n<\/code><\/pre>\n<p>\u4e0b\u9762\u662f\u4e00\u4e2a\u5b8c\u6574\u7684\u793a\u4f8b\u3002\u5b83\u4ece\u670d\u52a1\u5668\u52a0\u8f7d\u00a0<code>\/article\/xmlhttprequest\/example\/load<\/code>\uff0c\u5e76\u6253\u5370\u52a0\u8f7d\u8fdb\u5ea6\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ 1. \u521b\u5efa\u4e00\u4e2a new XMLHttpRequest \u5bf9\u8c61\nlet xhr = new XMLHttpRequest();\n\n\/\/ 2. \u914d\u7f6e\u5b83\uff1a\u4ece URL \/article\/...\/load GET-request\nxhr.open('GET', '\/article\/xmlhttprequest\/example\/load');\n\n\/\/ 3. \u901a\u8fc7\u7f51\u7edc\u53d1\u9001\u8bf7\u6c42\nxhr.send();\n\n\/\/ 4. \u5f53\u63a5\u6536\u5230\u54cd\u5e94\u540e\uff0c\u5c06\u8c03\u7528\u6b64\u51fd\u6570\nxhr.onload = function() {\n  if (xhr.status != 200) { \/\/ \u5206\u6790\u54cd\u5e94\u7684 HTTP \u72b6\u6001\n    alert(`Error ${xhr.status}: ${xhr.statusText}`); \/\/ \u4f8b\u5982 404: Not Found\n  } else { \/\/ \u663e\u793a\u7ed3\u679c\n    alert(`Done, got ${xhr.response.length} bytes`); \/\/ response \u662f\u670d\u52a1\u5668\u54cd\u5e94\n  }\n};\n\nxhr.onprogress = function(event) {\n  if (event.lengthComputable) {\n    alert(`Received ${event.loaded} of ${event.total} bytes`);\n  } else {\n    alert(`Received ${event.loaded} bytes`); \/\/ \u6ca1\u6709 Content-Length\n  }\n\n};\n\nxhr.onerror = function() {\n  alert(&quot;Request failed&quot;);\n};\n<\/code><\/pre>\n<p>\u4e00\u65e6\u670d\u52a1\u5668\u6709\u4e86\u54cd\u5e94\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u4ee5\u4e0b\u00a0<code>xhr<\/code>\u00a0\u5c5e\u6027\u4e2d\u63a5\u6536\u7ed3\u679c\uff1a<br \/>\n<code>status<\/code><br \/>\nHTTP \u72b6\u6001\u7801\uff08\u4e00\u4e2a\u6570\u5b57\uff09\uff1a<code>200<\/code>\uff0c<code>404<\/code>\uff0c<code>403<\/code>\u00a0\u7b49\uff0c\u5982\u679c\u51fa\u73b0\u975e HTTP \u9519\u8bef\uff0c\u5219\u4e3a\u00a0<code>0<\/code>\u3002<br \/>\n<code>statusText<\/code><br \/>\nHTTP \u72b6\u6001\u6d88\u606f\uff08\u4e00\u4e2a\u5b57\u7b26\u4e32\uff09\uff1a\u72b6\u6001\u7801\u4e3a\u00a0<code>200<\/code>\u00a0\u5bf9\u5e94\u4e8e\u00a0<code>OK<\/code>\uff0c<code>404<\/code>\u00a0\u5bf9\u5e94\u4e8e\u00a0<code>Not Found<\/code>\uff0c<code>403<\/code>\u00a0\u5bf9\u5e94\u4e8e\u00a0<code>Forbidden<\/code>\u3002<br \/>\n<code>response<\/code>\uff08\u65e7\u811a\u672c\u53ef\u80fd\u7528\u7684\u662f\u00a0<code>responseText<\/code>\uff09<br \/>\n\u670d\u52a1\u5668 response body\u3002<br \/>\n\u6211\u4eec\u8fd8\u53ef\u4ee5\u4f7f\u7528\u76f8\u5e94\u7684\u5c5e\u6027\u6307\u5b9a\u8d85\u65f6\uff08timeout\uff09\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.timeout = 10000; \/\/ timeout \u5355\u4f4d\u662f ms\uff0c\u6b64\u5904\u5373 10 \u79d2\n<\/code><\/pre>\n<p>\u5982\u679c\u5728\u7ed9\u5b9a\u65f6\u95f4\u5185\u8bf7\u6c42\u6ca1\u6709\u6210\u529f\u6267\u884c\uff0c\u8bf7\u6c42\u5c31\u4f1a\u88ab\u53d6\u6d88\uff0c\u5e76\u4e14\u89e6\u53d1\u00a0<code>timeout<\/code>\u00a0\u4e8b\u4ef6\u3002<\/p>\n<blockquote>\n<p>URL \u641c\u7d22\u53c2\u6570\uff08URL search parameters\uff09<br \/>\n\u4e3a\u4e86\u5411 URL \u6dfb\u52a0\u50cf\u00a0<code>?name=value<\/code>\u00a0\u8fd9\u6837\u7684\u53c2\u6570\uff0c\u5e76\u786e\u4fdd\u6b63\u786e\u7684\u7f16\u7801\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<a href=\"https:\/\/zh.javascript.info\/url\">URL<\/a>\u00a0\u5bf9\u8c61\uff1a<\/p>\n<\/blockquote>\n<pre><code class=\"language-js\">let url = new URL('https:\/\/google.com\/search');\nurl.searchParams.set('q', 'test me!');\n\n\/\/ \u53c2\u6570 'q' \u88ab\u7f16\u7801\nxhr.open('GET', url); \/\/ https:\/\/google.com\/search?q=test+me%21\n<\/code><\/pre>\n<h2>\u54cd\u5e94\u7c7b\u578b<\/h2>\n<p>\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>xhr.responseType<\/code>\u00a0\u5c5e\u6027\u6765\u8bbe\u7f6e\u54cd\u5e94\u683c\u5f0f\uff1a<\/p>\n<ul>\n<li><code>&quot;&quot;<\/code>\uff08\u9ed8\u8ba4\uff09\u2014\u2014 \u54cd\u5e94\u683c\u5f0f\u4e3a\u5b57\u7b26\u4e32\uff0c<\/li>\n<li><code>&quot;text&quot;<\/code>\u00a0\u2014\u2014 \u54cd\u5e94\u683c\u5f0f\u4e3a\u5b57\u7b26\u4e32\uff0c<\/li>\n<li><code>&quot;arraybuffer&quot;<\/code>\u00a0\u2014\u2014 \u54cd\u5e94\u683c\u5f0f\u4e3a\u00a0<code>ArrayBuffer<\/code>\uff08\u5bf9\u4e8e\u4e8c\u8fdb\u5236\u6570\u636e\uff0c\u8bf7\u53c2\u89c1\u00a0<a href=\"https:\/\/zh.javascript.info\/arraybuffer-binary-arrays\">ArrayBuffer\uff0c\u4e8c\u8fdb\u5236\u6570\u7ec4<\/a>\uff09\uff0c<\/li>\n<li><code>&quot;blob&quot;<\/code>\u00a0\u2014\u2014 \u54cd\u5e94\u683c\u5f0f\u4e3a\u00a0<code>Blob<\/code>\uff08\u5bf9\u4e8e\u4e8c\u8fdb\u5236\u6570\u636e\uff0c\u8bf7\u53c2\u89c1\u00a0<a href=\"https:\/\/zh.javascript.info\/blob\">Blob<\/a>\uff09\uff0c<\/li>\n<li><code>&quot;document&quot;<\/code>\u00a0\u2014\u2014 \u54cd\u5e94\u683c\u5f0f\u4e3a XML document\uff08\u53ef\u4ee5\u4f7f\u7528 XPath \u548c\u5176\u4ed6 XML \u65b9\u6cd5\uff09\u6216 HTML document\uff08\u57fa\u4e8e\u63a5\u6536\u6570\u636e\u7684 MIME \u7c7b\u578b\uff09<\/li>\n<li><code>&quot;json&quot;<\/code>\u00a0\u2014\u2014 \u54cd\u5e94\u683c\u5f0f\u4e3a JSON\uff08\u81ea\u52a8\u89e3\u6790\uff09\u3002<br \/>\n\u4f8b\u5982\uff0c\u6211\u4eec\u4ee5 JSON \u683c\u5f0f\u83b7\u53d6\u54cd\u5e94\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let xhr = new XMLHttpRequest();\n\nxhr.open('GET', '\/article\/xmlhttprequest\/example\/json');\n\nxhr.responseType = 'json';\n\nxhr.send();\n\n\/\/ \u54cd\u5e94\u4e3a {&quot;message&quot;: &quot;Hello, world!&quot;}\nxhr.onload = function() {\n  let responseObj = xhr.response;\n  alert(responseObj.message); \/\/ Hello, world!\n};\n<\/code><\/pre>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u5728\u65e7\u7684\u811a\u672c\u4e2d\uff0c\u4f60\u53ef\u80fd\u4f1a\u770b\u5230\u00a0<code>xhr.responseText<\/code>\uff0c\u751a\u81f3\u4f1a\u770b\u5230\u00a0<code>xhr.responseXML<\/code>\u00a0\u5c5e\u6027\u3002<br \/>\n\u5b83\u4eec\u662f\u7531\u4e8e\u5386\u53f2\u539f\u56e0\u800c\u5b58\u5728\u7684\uff0c\u4ee5\u83b7\u53d6\u5b57\u7b26\u4e32\u6216 XML \u6587\u6863\u3002\u5982\u4eca\uff0c\u6211\u4eec\u5e94\u8be5\u5728\u00a0<code>xhr.responseType<\/code>\u00a0\u4e2d\u8bbe\u7f6e\u683c\u5f0f\uff0c\u7136\u540e\u5c31\u80fd\u83b7\u53d6\u5982\u4e0a\u6240\u793a\u7684\u00a0<code>xhr.response<\/code>\u00a0\u4e86\u3002<\/p>\n<\/blockquote>\n<h2>readyState<\/h2>\n<p><code>XMLHttpRequest<\/code>\u00a0\u7684\u72b6\u6001\uff08state\uff09\u4f1a\u968f\u7740\u5b83\u7684\u5904\u7406\u8fdb\u5ea6\u53d8\u5316\u800c\u53d8\u5316\u3002\u53ef\u4ee5\u901a\u8fc7\u00a0<code>xhr.readyState<\/code>\u00a0\u6765\u4e86\u89e3\u5f53\u524d\u72b6\u6001\u3002<br \/>\n<a href=\"https:\/\/xhr.spec.whatwg.org\/#states\">\u89c4\u8303<\/a>\u00a0\u4e2d\u63d0\u5230\u7684\u6240\u6709\u72b6\u6001\u5982\u4e0b\uff1a<\/p>\n<pre><code class=\"language-js\">UNSENT = 0; \/\/ \u521d\u59cb\u72b6\u6001\nOPENED = 1; \/\/ open \u88ab\u8c03\u7528\nHEADERS_RECEIVED = 2; \/\/ \u63a5\u6536\u5230 response header\nLOADING = 3; \/\/ \u54cd\u5e94\u6b63\u5728\u88ab\u52a0\u8f7d\uff08\u63a5\u6536\u5230\u4e00\u4e2a\u6570\u636e\u5305\uff09\nDONE = 4; \/\/ \u8bf7\u6c42\u5b8c\u6210\n<\/code><\/pre>\n<p><code>XMLHttpRequest<\/code>\u00a0\u5bf9\u8c61\u4ee5\u00a0<code>0<\/code>\u00a0\u2192\u00a0<code>1<\/code>\u00a0\u2192\u00a0<code>2<\/code>\u00a0\u2192\u00a0<code>3<\/code>\u00a0\u2192 \u2026 \u2192\u00a0<code>3<\/code>\u00a0\u2192\u00a0<code>4<\/code>\u00a0\u7684\u987a\u5e8f\u5728\u5b83\u4eec\u4e4b\u95f4\u8f6c\u53d8\u3002\u6bcf\u5f53\u901a\u8fc7\u7f51\u7edc\u63a5\u6536\u5230\u4e00\u4e2a\u6570\u636e\u5305\uff0c\u5c31\u4f1a\u91cd\u590d\u4e00\u6b21\u72b6\u6001\u00a0<code>3<\/code>\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>readystatechange<\/code>\u00a0\u4e8b\u4ef6\u6765\u8ddf\u8e2a\u5b83\u4eec\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.onreadystatechange = function() {\n  if (xhr.readyState == 3) {\n    \/\/ \u52a0\u8f7d\u4e2d\n  }\n  if (xhr.readyState == 4) {\n    \/\/ \u8bf7\u6c42\u5b8c\u6210\n  }\n};\n<\/code><\/pre>\n<p>\u4f60\u53ef\u80fd\u5728\u975e\u5e38\u8001\u7684\u4ee3\u7801\u4e2d\u627e\u5230\u00a0<code>readystatechange<\/code>\u00a0\u8fd9\u6837\u7684\u4e8b\u4ef6\u76d1\u542c\u5668\uff0c\u5b83\u7684\u5b58\u5728\u662f\u6709\u5386\u53f2\u539f\u56e0\u7684\uff0c\u56e0\u4e3a\u66fe\u7ecf\u6709\u5f88\u957f\u4e00\u6bb5\u65f6\u95f4\u90fd\u6ca1\u6709\u00a0<code>load<\/code>\u00a0\u4ee5\u53ca\u5176\u4ed6\u4e8b\u4ef6\u3002\u5982\u4eca\uff0c\u5b83\u5df2\u88ab\u00a0<code>load\/error\/progress<\/code>\u00a0\u4e8b\u4ef6\u5904\u7406\u7a0b\u5e8f\u6240\u66ff\u4ee3\u3002<\/p>\n<h2>\u4e2d\u6b62\u8bf7\u6c42 Aborting<\/h2>\n<p>\u6211\u4eec\u53ef\u4ee5\u968f\u65f6\u7ec8\u6b62\u8bf7\u6c42\u3002\u8c03\u7528\u00a0<code>xhr.abort()<\/code>\u00a0\u5373\u53ef\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.abort(); \/\/ \u7ec8\u6b62\u8bf7\u6c42\n<\/code><\/pre>\n<p>\u5b83\u4f1a\u89e6\u53d1\u00a0<code>abort<\/code>\u00a0\u4e8b\u4ef6\uff0c\u4e14\u00a0<code>xhr.status<\/code>\u00a0\u53d8\u4e3a\u00a0<code>0<\/code>\u3002<\/p>\n<h2>\u540c\u6b65\u8bf7\u6c42<\/h2>\n<p>\u5982\u679c\u5728\u00a0<code>open<\/code>\u00a0\u65b9\u6cd5\u4e2d\u5c06\u7b2c\u4e09\u4e2a\u53c2\u6570\u00a0<code>async<\/code>\u00a0\u8bbe\u7f6e\u4e3a\u00a0<code>false<\/code>\uff0c\u90a3\u4e48\u8bf7\u6c42\u5c31\u4f1a\u4ee5\u540c\u6b65\u7684\u65b9\u5f0f\u8fdb\u884c\u3002<br \/>\n\u6362\u53e5\u8bdd\u8bf4\uff0cJavaScript \u6267\u884c\u5728\u00a0<code>send()<\/code>\u00a0\u5904\u6682\u505c\uff0c\u5e76\u5728\u6536\u5230\u54cd\u5e94\u540e\u6062\u590d\u6267\u884c\u3002\u8fd9\u6709\u70b9\u513f\u50cf\u00a0<code>alert<\/code>\u00a0\u6216\u00a0<code>prompt<\/code>\u00a0\u547d\u4ee4\u3002<br \/>\n\u4e0b\u9762\u662f\u91cd\u5199\u7684\u793a\u4f8b\uff0c<code>open<\/code>\u00a0\u7684\u7b2c\u4e09\u4e2a\u53c2\u6570\u4e3a\u00a0<code>false<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">let xhr = new XMLHttpRequest();\n\nxhr.open('GET', '\/article\/xmlhttprequest\/hello.txt', false);\n\ntry {\n  xhr.send();\n  if (xhr.status != 200) {\n    alert(`Error ${xhr.status}: ${xhr.statusText}`);\n  } else {\n    alert(xhr.response);\n  }\n} catch(err) { \/\/ \u4ee3\u66ff onerror\n  alert(&quot;Request failed&quot;);\n}\n<\/code><\/pre>\n<p>\u8fd9\u770b\u8d77\u6765\u597d\u50cf\u4e0d\u9519\uff0c\u4f46\u662f\u5f88\u5c11\u4f7f\u7528\u540c\u6b65\u8c03\u7528\uff0c\u56e0\u4e3a\u5b83\u4eec\u4f1a\u963b\u585e\u9875\u9762\u5185\u7684 JavaScript\uff0c\u76f4\u5230\u52a0\u8f7d\u5b8c\u6210\u3002\u5728\u67d0\u4e9b\u6d4f\u89c8\u5668\u4e2d\uff0c\u6eda\u52a8\u53ef\u80fd\u65e0\u6cd5\u6b63\u5e38\u8fdb\u884c\u3002\u5982\u679c\u4e00\u4e2a\u540c\u6b65\u8c03\u7528\u6267\u884c\u65f6\u95f4\u8fc7\u957f\uff0c\u6d4f\u89c8\u5668\u53ef\u80fd\u4f1a\u5efa\u8bae\u5173\u95ed\u201c\u6302\u8d77\uff08hanging\uff09\u201d\u7684\u7f51\u9875\u3002<br \/>\n<code>XMLHttpRequest<\/code>\u00a0\u7684\u5f88\u591a\u9ad8\u7ea7\u529f\u80fd\u5728\u540c\u6b65\u8bf7\u6c42\u4e2d\u90fd\u4e0d\u53ef\u7528\uff0c\u4f8b\u5982\u5411\u5176\u4ed6\u57df\u53d1\u8d77\u8bf7\u6c42\u6216\u8005\u8bbe\u7f6e\u8d85\u65f6\u3002\u5e76\u4e14\uff0c\u6b63\u5982\u4f60\u6240\u770b\u5230\u7684\uff0c\u6ca1\u6709\u8fdb\u5ea6\u6307\u793a\u3002<br \/>\n\u57fa\u4e8e\u8fd9\u4e9b\u539f\u56e0\uff0c\u540c\u6b65\u8bf7\u6c42\u4f7f\u7528\u7684\u975e\u5e38\u5c11\uff0c\u51e0\u4e4e\u4ece\u4e0d\u4f7f\u7528\u3002\u5728\u8fd9\u6211\u4eec\u5c31\u4e0d\u518d\u8ba8\u8bba\u5b83\u4e86\u3002<\/p>\n<h2>HTTP-header<\/h2>\n<p><code>XMLHttpRequest<\/code>\u00a0\u5141\u8bb8\u53d1\u9001\u81ea\u5b9a\u4e49 header\uff0c\u5e76\u4e14\u53ef\u4ee5\u4ece\u54cd\u5e94\u4e2d\u8bfb\u53d6 header\u3002<br \/>\nHTTP-header \u6709\u4e09\u79cd\u65b9\u6cd5\uff1a<br \/>\n<code>setRequestHeader(name, value)<\/code><br \/>\n\u4f7f\u7528\u7ed9\u5b9a\u7684\u00a0<code>name<\/code>\u00a0\u548c\u00a0<code>value<\/code>\u00a0\u8bbe\u7f6e request header\u3002<br \/>\n\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.setRequestHeader('Content-Type', 'application\/json');\n<\/code><\/pre>\n<blockquote>\n<p>Header \u7684\u9650\u5236<br \/>\n\u4e00\u4e9b header \u662f\u7531\u6d4f\u89c8\u5668\u4e13\u95e8\u7ba1\u7406\u7684\uff0c\u4f8b\u5982\u00a0<code>Referer<\/code>\u00a0\u548c\u00a0<code>Host<\/code>\u3002 \u5b8c\u6574\u5217\u8868\u8bf7\u89c1\u00a0<a href=\"https:\/\/xhr.spec.whatwg.org\/#the-setrequestheader()-method\">\u89c4\u8303<\/a>\u3002<br \/>\n\u4e3a\u4e86\u7528\u6237\u5b89\u5168\u548c\u8bf7\u6c42\u7684\u6b63\u786e\u6027\uff0c<code>XMLHttpRequest<\/code>\u00a0\u4e0d\u5141\u8bb8\u66f4\u6539\u5b83\u4eec\u3002<\/p>\n<\/blockquote>\n<blockquote>\n<p>\u4e0d\u80fd\u79fb\u9664 header<br \/>\n<code>XMLHttpRequest<\/code>\u00a0\u7684\u53e6\u4e00\u4e2a\u7279\u70b9\u662f\u4e0d\u80fd\u64a4\u9500\u00a0<code>setRequestHeader<\/code>\u3002<br \/>\n\u4e00\u65e6\u8bbe\u7f6e\u4e86 header\uff0c\u5c31\u65e0\u6cd5\u64a4\u9500\u4e86\u3002\u5176\u4ed6\u8c03\u7528\u4f1a\u5411 header \u4e2d\u6dfb\u52a0\u4fe1\u606f\uff0c\u4f46\u4e0d\u4f1a\u8986\u76d6\u5b83\u3002<br \/>\n\u4f8b\u5982\uff1a<\/p>\n<\/blockquote>\n<pre><code class=\"language-js\">xhr.setRequestHeader('X-Auth', '123');\nxhr.setRequestHeader('X-Auth', '456');\n\n\/\/ header \u5c06\u662f\uff1a\n\/\/ X-Auth: 123, 456\n<\/code><\/pre>\n<p><code>getResponseHeader(name)<\/code><br \/>\n\u83b7\u53d6\u5177\u6709\u7ed9\u5b9a\u00a0<code>name<\/code>\u00a0\u7684 header\uff08<code>Set-Cookie<\/code>\u00a0\u548c\u00a0<code>Set-Cookie2<\/code>\u00a0\u9664\u5916\uff09\u3002<br \/>\n\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.getResponseHeader('Content-Type')\n<\/code><\/pre>\n<p><code>getAllResponseHeaders()<\/code><br \/>\n\u8fd4\u56de\u9664\u00a0<code>Set-Cookie<\/code>\u00a0\u548c\u00a0<code>Set-Cookie2<\/code>\u00a0\u5916\u7684\u6240\u6709 response header\u3002<br \/>\nheader \u4ee5\u5355\u884c\u5f62\u5f0f\u8fd4\u56de\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">Cache-Control: max-age=31536000\nContent-Length: 4260\nContent-Type: image\/png\nDate: Sat, 08 Sep 2012 16:53:16 GMT\n<\/code><\/pre>\n<p>header \u4e4b\u95f4\u7684\u6362\u884c\u7b26\u59cb\u7ec8\u4e3a\u00a0<code>&quot;\\r\\n&quot;<\/code>\uff08\u4e0d\u4f9d\u8d56\u4e8e\u64cd\u4f5c\u7cfb\u7edf\uff09\uff0c\u6240\u4ee5\u6211\u4eec\u53ef\u4ee5\u5f88\u5bb9\u6613\u5730\u5c06\u5176\u62c6\u5206\u4e3a\u5355\u72ec\u7684 header\u3002name \u548c value \u4e4b\u95f4\u603b\u662f\u4ee5\u5192\u53f7\u540e\u8ddf\u4e00\u4e2a\u7a7a\u683c\u00a0<code>&quot;: &quot;<\/code>\u00a0\u5206\u9694\u3002\u8fd9\u662f\u6807\u51c6\u683c\u5f0f\u3002<br \/>\n\u56e0\u6b64\uff0c\u5982\u679c\u6211\u4eec\u60f3\u8981\u83b7\u53d6\u5177\u6709 name\/value \u5bf9\u7684\u5bf9\u8c61\uff0c\u5219\u9700\u8981\u7528\u4e00\u70b9 JavaScript \u4ee3\u7801\u6765\u5904\u7406\u5b83\u4eec\u3002<br \/>\n\u50cf\u8fd9\u6837\uff08\u5047\u8bbe\u5982\u679c\u4e24\u4e2a header \u5177\u6709\u76f8\u540c\u7684\u540d\u79f0\uff0c\u90a3\u4e48\u540e\u8005\u5c31\u4f1a\u8986\u76d6\u524d\u8005\uff09\uff1a<\/p>\n<pre><code class=\"language-js\">let headers = xhr\n  .getAllResponseHeaders()\n  .split('\\r\\n')\n  .reduce((result, current) =&gt; {\n    let [name, value] = current.split(': ');\n    result[name] = value;\n    return result;\n  }, {});\n\n\/\/ headers['Content-Type'] = 'image\/png'\n<\/code><\/pre>\n<h2>POST,FormData<\/h2>\n<p>\u8981\u5efa\u7acb\u4e00\u4e2a POST \u8bf7\u6c42\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5185\u5efa\u7684\u00a0<a href=\"https:\/\/developer.mozilla.org\/zh\/docs\/Web\/API\/FormData\">FormData<\/a>\u00a0\u5bf9\u8c61\u3002<br \/>\n\u8bed\u6cd5\u4e3a\uff1a<\/p>\n<pre><code class=\"language-js\">let formData = new FormData([form]); \/\/ \u521b\u5efa\u4e00\u4e2a\u5bf9\u8c61\uff0c\u53ef\u4ee5\u9009\u62e9\u4ece &lt;form&gt; \u4e2d\u83b7\u53d6\u6570\u636e\nformData.append(name, value); \/\/ \u9644\u52a0\u4e00\u4e2a\u5b57\u6bb5\n<\/code><\/pre>\n<p>\u6211\u4eec\u521b\u5efa\u5b83\uff0c\u53ef\u4ee5\u9009\u62e9\u4ece\u4e00\u4e2a\u8868\u5355\u4e2d\u83b7\u53d6\u6570\u636e\uff0c\u5982\u679c\u9700\u8981\uff0c\u8fd8\u53ef\u4ee5\u00a0<code>append<\/code>\u00a0\u66f4\u591a\u5b57\u6bb5\uff0c\u7136\u540e\uff1a<\/p>\n<ol>\n<li><code>xhr.open('POST', ...)<\/code>\u00a0\u2014\u2014 \u4f7f\u7528\u00a0<code>POST<\/code>\u00a0\u65b9\u6cd5\u3002<\/li>\n<li><code>xhr.send(formData)<\/code>\u00a0\u5c06\u8868\u5355\u53d1\u9001\u5230\u670d\u52a1\u5668\u3002<br \/>\n\u4f8b\u5982\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-html\">&lt;form name=&quot;person&quot;&gt;\n  &lt;input name=&quot;name&quot; value=&quot;John&quot;&gt;\n  &lt;input name=&quot;surname&quot; value=&quot;Smith&quot;&gt;\n&lt;\/form&gt;\n\n&lt;script&gt;\n  \/\/ \u4ece\u8868\u5355\u9884\u586b\u5145 FormData\n  let formData = new FormData(document.forms.person);\n\n  \/\/ \u9644\u52a0\u4e00\u4e2a\u5b57\u6bb5\n  formData.append(&quot;middle&quot;, &quot;Lee&quot;);\n\n  \/\/ \u5c06\u5176\u53d1\u9001\u51fa\u53bb\n  let xhr = new XMLHttpRequest();\n  xhr.open(&quot;POST&quot;, &quot;\/article\/xmlhttprequest\/post\/user&quot;);\n  xhr.send(formData);\n\n  xhr.onload = () =&gt; alert(xhr.response);\n&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u4ee5\u00a0<code>multipart\/form-data<\/code>\u00a0\u7f16\u7801\u53d1\u9001\u8868\u5355\u3002<br \/>\n\u6216\u8005\uff0c\u5982\u679c\u6211\u4eec\u66f4\u559c\u6b22 JSON\uff0c\u90a3\u4e48\u53ef\u4ee5\u4f7f\u7528\u00a0<code>JSON.stringify<\/code>\u00a0\u5e76\u4ee5\u5b57\u7b26\u4e32\u5f62\u5f0f\u53d1\u9001\u3002<br \/>\n\u53ea\u662f\uff0c\u4e0d\u8981\u5fd8\u8bb0\u8bbe\u7f6e header\u00a0<code>Content-Type: application\/json<\/code>\uff0c\u53ea\u8981\u6709\u4e86\u5b83\uff0c\u5f88\u591a\u670d\u52a1\u7aef\u6846\u67b6\u90fd\u80fd\u81ea\u52a8\u89e3\u7801 JSON\uff1a<\/p>\n<pre><code class=\"language-js\">let xhr = new XMLHttpRequest();\n\nlet json = JSON.stringify({\n  name: &quot;John&quot;,\n  surname: &quot;Smith&quot;\n});\n\nxhr.open(&quot;POST&quot;, '\/submit')\nxhr.setRequestHeader('Content-type', 'application\/json; charset=utf-8');\n\nxhr.send(json);\n<\/code><\/pre>\n<p><code>.send(body)<\/code>\u00a0\u65b9\u6cd5\u5c31\u50cf\u4e00\u4e2a\u975e\u5e38\u6742\u98df\u6027\u7684\u52a8\u7269\u3002\u5b83\u51e0\u4e4e\u53ef\u4ee5\u53d1\u9001\u4efb\u4f55\u00a0<code>body<\/code>\uff0c\u5305\u62ec\u00a0<code>Blob<\/code>\u00a0\u548c\u00a0<code>BufferSource<\/code>\u00a0\u5bf9\u8c61\u3002<\/p>\n<h2>\u4e0a\u4f20\u8fdb\u5ea6<\/h2>\n<p><code>progress<\/code>\u00a0\u4e8b\u4ef6\u4ec5\u5728\u4e0b\u8f7d\u9636\u6bb5\u89e6\u53d1\u3002<br \/>\n\u4e5f\u5c31\u662f\u8bf4\uff1a\u5982\u679c\u6211\u4eec\u00a0<code>POST<\/code>\u00a0\u4e00\u4e9b\u5185\u5bb9\uff0c<code>XMLHttpRequest<\/code>\u00a0\u9996\u5148\u4e0a\u4f20\u6211\u4eec\u7684\u6570\u636e\uff08request body\uff09\uff0c\u7136\u540e\u4e0b\u8f7d\u54cd\u5e94\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u8981\u4e0a\u4f20\u7684\u4e1c\u897f\u5f88\u5927\uff0c\u90a3\u4e48\u6211\u4eec\u80af\u5b9a\u4f1a\u5bf9\u8ddf\u8e2a\u4e0a\u4f20\u8fdb\u5ea6\u611f\u5174\u8da3\u3002\u4f46\u662f\u00a0<code>xhr.onprogress<\/code>\u00a0\u5728\u8fd9\u91cc\u5e76\u4e0d\u8d77\u4f5c\u7528\u3002<br \/>\n\u8fd9\u91cc\u6709\u53e6\u4e00\u4e2a\u5bf9\u8c61\uff0c\u5b83\u6ca1\u6709\u65b9\u6cd5\uff0c\u5b83\u4e13\u95e8\u7528\u4e8e\u8ddf\u8e2a\u4e0a\u4f20\u4e8b\u4ef6\uff1a<code>xhr.upload<\/code>\u3002<br \/>\n\u5b83\u4f1a\u751f\u6210\u4e8b\u4ef6\uff0c\u7c7b\u4f3c\u4e8e\u00a0<code>xhr<\/code>\uff0c\u4f46\u662f\u00a0<code>xhr.upload<\/code>\u00a0\u4ec5\u5728\u4e0a\u4f20\u65f6\u89e6\u53d1\u5b83\u4eec\uff1a<\/p>\n<ul>\n<li><code>loadstart<\/code>\u00a0\u2014\u2014 \u4e0a\u4f20\u5f00\u59cb\u3002<\/li>\n<li><code>progress<\/code>\u00a0\u2014\u2014 \u4e0a\u4f20\u671f\u95f4\u5b9a\u671f\u89e6\u53d1\u3002<\/li>\n<li><code>abort<\/code>\u00a0\u2014\u2014 \u4e0a\u4f20\u4e2d\u6b62\u3002<\/li>\n<li><code>error<\/code>\u00a0\u2014\u2014 \u975e HTTP \u9519\u8bef\u3002<\/li>\n<li><code>load<\/code>\u00a0\u2014\u2014 \u4e0a\u4f20\u6210\u529f\u5b8c\u6210\u3002<\/li>\n<li><code>timeout<\/code>\u00a0\u2014\u2014 \u4e0a\u4f20\u8d85\u65f6\uff08\u5982\u679c\u8bbe\u7f6e\u4e86\u00a0<code>timeout<\/code>\u00a0\u5c5e\u6027\uff09\u3002<\/li>\n<li><code>loadend<\/code>\u00a0\u2014\u2014 \u4e0a\u4f20\u5b8c\u6210\uff0c\u65e0\u8bba\u6210\u529f\u8fd8\u662f error\u3002<br \/>\nhandler \u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">xhr.upload.onprogress = function(event) {\n  alert(`Uploaded ${event.loaded} of ${event.total} bytes`);\n};\n\nxhr.upload.onload = function() {\n  alert(`Upload finished successfully.`);\n};\n\nxhr.upload.onerror = function() {\n  alert(`Error during the upload: ${xhr.status}`);\n};\n<\/code><\/pre>\n<h2>\u8de8\u6e90\u8bf7\u6c42<\/h2>\n<p><code>XMLHttpRequest<\/code>\u00a0\u53ef\u4ee5\u4f7f\u7528\u548c\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">fetch<\/a>\u00a0\u76f8\u540c\u7684 CORS \u7b56\u7565\u8fdb\u884c\u8de8\u6e90\u8bf7\u6c42\u3002<br \/>\n\u5c31\u50cf\u00a0<code>fetch<\/code>\u00a0\u4e00\u6837\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u4e0d\u4f1a\u5c06 cookie \u548c HTTP \u6388\u6743\u53d1\u9001\u5230\u5176\u4ed6\u57df\u3002\u8981\u542f\u7528\u5b83\u4eec\uff0c\u53ef\u4ee5\u5c06\u00a0<code>xhr.withCredentials<\/code>\u00a0\u8bbe\u7f6e\u4e3a\u00a0<code>true<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">let xhr = new XMLHttpRequest();\nxhr.withCredentials = true;\n\nxhr.open('POST', 'http:\/\/anywhere.com\/request');\n...\n<\/code><\/pre>\n<p>\u6709\u5173\u8de8\u6e90 header \u7684\u8be6\u7ec6\u4fe1\u606f\uff0c\u8bf7\u89c1\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">Fetch\uff1a\u8de8\u6e90\u8bf7\u6c42<\/a>\u00a0\u4e00\u7ae0\u3002<\/p>\n<h1>\u53ef\u6062\u590d\u7684\u6587\u4ef6\u4e0a\u4f20<\/h1>\n<p>\u4f7f\u7528\u00a0<code>fetch<\/code>\u00a0\u65b9\u6cd5\u6765\u4e0a\u4f20\u6587\u4ef6\u76f8\u5f53\u5bb9\u6613\u3002<br \/>\n\u8fde\u63a5\u65ad\u5f00\u540e\u5982\u4f55\u6062\u590d\u4e0a\u4f20\uff1f\u8fd9\u91cc\u6ca1\u6709\u5bf9\u6b64\u7684\u5185\u5efa\u9009\u9879\uff0c\u4f46\u662f\u6211\u4eec\u6709\u5b9e\u73b0\u5b83\u7684\u4e00\u4e9b\u65b9\u5f0f\u3002<br \/>\n\u5bf9\u4e8e\u5927\u6587\u4ef6\uff08\u5982\u679c\u6211\u4eec\u53ef\u80fd\u9700\u8981\u6062\u590d\uff09\uff0c\u53ef\u6062\u590d\u7684\u4e0a\u4f20\u5e94\u8be5\u5e26\u6709\u4e0a\u4f20\u8fdb\u5ea6\u63d0\u793a\u3002\u7531\u4e8e\u00a0<code>fetch<\/code>\u00a0\u4e0d\u5141\u8bb8\u8ddf\u8e2a\u4e0a\u4f20\u8fdb\u5ea6\uff0c\u6211\u4eec\u5c06\u4f1a\u4f7f\u7528\u00a0<a href=\"https:\/\/zh.javascript.info\/xmlhttprequest\">XMLHttpRequest<\/a>\u3002<\/p>\n<h2>\u4e0d\u592a\u5b9e\u7528\u7684\u8fdb\u5ea6\u4e8b\u4ef6<\/h2>\n<p>\u8981\u6062\u590d\u4e0a\u4f20\uff0c\u6211\u4eec\u9700\u8981\u77e5\u9053\u5728\u8fde\u63a5\u65ad\u5f00\u524d\u5df2\u7ecf\u4e0a\u4f20\u4e86\u591a\u5c11\u3002<br \/>\n\u6211\u4eec\u6709\u00a0<code>xhr.upload.onprogress<\/code>\u00a0\u6765\u8ddf\u8e2a\u4e0a\u4f20\u8fdb\u5ea6\u3002<br \/>\n\u4e0d\u5e78\u7684\u662f\uff0c\u5b83\u4e0d\u4f1a\u5e2e\u52a9\u6211\u4eec\u5728\u6b64\u5904\u6062\u590d\u4e0a\u4f20\uff0c\u56e0\u4e3a\u5b83\u4f1a\u5728\u6570\u636e\u00a0<strong>\u88ab\u53d1\u9001<\/strong>\u00a0\u65f6\u89e6\u53d1\uff0c\u4f46\u662f\u670d\u52a1\u5668\u662f\u5426\u63a5\u6536\u5230\u4e86\uff1f\u6d4f\u89c8\u5668\u5e76\u4e0d\u77e5\u9053\u3002<br \/>\n\u6216\u8bb8\u5b83\u662f\u7531\u672c\u5730\u7f51\u7edc\u4ee3\u7406\u7f13\u51b2\u7684\uff08buffered\uff09\uff0c\u6216\u8005\u53ef\u80fd\u662f\u8fdc\u7a0b\u670d\u52a1\u5668\u8fdb\u7a0b\u521a\u521a\u7ec8\u6b62\u800c\u65e0\u6cd5\u5904\u7406\u5b83\u4eec\uff0c\u4ea6\u6216\u662f\u5b83\u5728\u4e2d\u95f4\u4e22\u5931\u4e86\uff0c\u5e76\u6ca1\u6709\u5230\u8fbe\u670d\u52a1\u5668\u3002<br \/>\n\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u6b64\u4e8b\u4ef6\u4ec5\u9002\u7528\u4e8e\u663e\u793a\u4e00\u4e2a\u597d\u770b\u7684\u8fdb\u5ea6\u6761\u3002<br \/>\n\u8981\u6062\u590d\u4e0a\u4f20\uff0c\u6211\u4eec\u9700\u8981\u00a0<strong>\u786e\u5207\u5730<\/strong>\u00a0\u77e5\u9053\u670d\u52a1\u5668\u63a5\u6536\u7684\u5b57\u8282\u6570\u3002\u800c\u4e14\u53ea\u6709\u670d\u52a1\u5668\u80fd\u544a\u8bc9\u6211\u4eec\uff0c\u56e0\u6b64\uff0c\u6211\u4eec\u5c06\u53d1\u51fa\u4e00\u4e2a\u989d\u5916\u7684\u8bf7\u6c42\u3002<\/p>\n<h2>\u7b97\u6cd5<\/h2>\n<ol>\n<li>\u9996\u5148\uff0c\u521b\u5efa\u4e00\u4e2a\u6587\u4ef6 id\uff0c\u4ee5\u552f\u4e00\u5730\u6807\u8bc6\u6211\u4eec\u8981\u4e0a\u4f20\u7684\u6587\u4ef6\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">let fileId = file.name + '-' + file.size + '-' + file.lastModified;\n<\/code><\/pre>\n<p>\u5728\u6062\u590d\u4e0a\u4f20\u65f6\u9700\u8981\u7528\u5230\u5b83\uff0c\u4ee5\u544a\u8bc9\u670d\u52a1\u5668\u6211\u4eec\u8981\u6062\u590d\u7684\u5185\u5bb9\u3002<br \/>\n\u5982\u679c\u540d\u79f0\uff0c\u6216\u5927\u5c0f\uff0c\u6216\u6700\u540e\u4e00\u6b21\u4fee\u6539\u65f6\u95f4\u53d1\u751f\u4e86\u66f4\u6539\uff0c\u5219\u5c06\u6709\u53e6\u4e00\u4e2a\u00a0<code>fileId<\/code>\u3002<br \/>\n2. \u5411\u670d\u52a1\u5668\u53d1\u9001\u4e00\u4e2a\u8bf7\u6c42\uff0c\u8be2\u95ee\u5b83\u5df2\u7ecf\u6709\u4e86\u591a\u5c11\u5b57\u8282\uff0c\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">let response = await fetch('status', {\n  headers: {\n    'X-File-Id': fileId\n  }\n});\n\n\/\/ \u670d\u52a1\u5668\u5df2\u6709\u7684\u5b57\u8282\u6570\nlet startByte = +await response.text();\n<\/code><\/pre>\n<p>\u8fd9\u5047\u8bbe\u670d\u52a1\u5668\u901a\u8fc7\u00a0<code>X-File-Id<\/code>\u00a0header \u8ddf\u8e2a\u6587\u4ef6\u4e0a\u4f20\u3002\u5e94\u8be5\u5728\u670d\u52a1\u7aef\u5b9e\u73b0\u3002<br \/>\n\u5982\u679c\u670d\u52a1\u5668\u4e0a\u5c1a\u4e0d\u5b58\u5728\u8be5\u6587\u4ef6\uff0c\u5219\u670d\u52a1\u5668\u54cd\u5e94\u5e94\u4e3a\u00a0<code>0<\/code>\u3002<br \/>\n3. \u7136\u540e\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>Blob<\/code>\u00a0\u548c\u00a0<code>slice<\/code>\u00a0\u65b9\u6cd5\u6765\u53d1\u9001\u4ece\u00a0<code>startByte<\/code>\u00a0\u5f00\u59cb\u7684\u6587\u4ef6\uff1a<\/p>\n<pre><code class=\"language-js\">xhr.open(&quot;POST&quot;, &quot;upload&quot;, true);\n\n\/\/ \u6587\u4ef6 id\uff0c\u4ee5\u4fbf\u670d\u52a1\u5668\u77e5\u9053\u6211\u4eec\u8981\u6062\u590d\u7684\u662f\u54ea\u4e2a\u6587\u4ef6\nxhr.setRequestHeader('X-File-Id', fileId);\n\n\/\/ \u53d1\u9001\u6211\u4eec\u8981\u4ece\u54ea\u4e2a\u5b57\u8282\u5f00\u59cb\u6062\u590d\uff0c\u56e0\u6b64\u670d\u52a1\u5668\u77e5\u9053\u6211\u4eec\u6b63\u5728\u6062\u590d\nxhr.setRequestHeader('X-Start-Byte', startByte);\n\nxhr.upload.onprogress = (e) =&gt; {\n  console.log(`Uploaded ${startByte + e.loaded} of ${startByte + e.total}`);\n};\n\n\/\/ \u6587\u4ef6\u53ef\u4ee5\u662f\u6765\u81ea input.files[0]\uff0c\u6216\u8005\u53e6\u4e00\u4e2a\u6e90\nxhr.send(file.slice(startByte));\n<\/code><\/pre>\n<p>\u8fd9\u91cc\u6211\u4eec\u5c06\u6587\u4ef6 id \u4f5c\u4e3a\u00a0<code>X-File-Id<\/code>\u00a0\u53d1\u9001\u7ed9\u670d\u52a1\u5668\uff0c\u6240\u4ee5\u670d\u52a1\u5668\u77e5\u9053\u6211\u4eec\u6b63\u5728\u4e0a\u4f20\u54ea\u4e2a\u6587\u4ef6\uff0c\u5e76\u4e14\uff0c\u6211\u4eec\u8fd8\u5c06\u8d77\u59cb\u5b57\u8282\u4f5c\u4e3a\u00a0<code>X-Start-Byte<\/code>\u00a0\u53d1\u9001\u7ed9\u670d\u52a1\u5668\uff0c\u6240\u4ee5\u670d\u52a1\u5668\u77e5\u9053\u6211\u4eec\u4e0d\u662f\u91cd\u65b0\u4e0a\u4f20\u5b83\uff0c\u800c\u662f\u6062\u590d\u5176\u4e0a\u4f20\u3002<br \/>\n\u670d\u52a1\u5668\u5e94\u8be5\u68c0\u67e5\u5176\u8bb0\u5f55\uff0c\u5982\u679c\u6709\u4e00\u4e2a\u4e0a\u4f20\u7684\u8be5\u6587\u4ef6\uff0c\u5e76\u4e14\u5f53\u524d\u5df2\u4e0a\u4f20\u7684\u6587\u4ef6\u5927\u5c0f\u6070\u597d\u662f\u00a0<code>X-Start-Byte<\/code>\uff0c\u90a3\u4e48\u5c31\u5c06\u6570\u636e\u9644\u52a0\u5230\u8be5\u6587\u4ef6\u3002<\/p>\n<h2>\u957f\u8f6e\u8be2 Long polling<\/h2>\n<p>\u957f\u8f6e\u8be2\u662f\u4e0e\u670d\u52a1\u5668\u4fdd\u6301\u6301\u4e45\u8fde\u63a5\u7684\u6700\u7b80\u5355\u7684\u65b9\u5f0f\uff0c\u5b83\u4e0d\u4f7f\u7528\u4efb\u4f55\u7279\u5b9a\u7684\u534f\u8bae\uff0c\u4f8b\u5982 WebSocket \u6216\u8005 Server Sent Event\u3002<br \/>\n\u5b83\u5f88\u5bb9\u6613\u5b9e\u73b0\uff0c\u5728\u5f88\u591a\u573a\u666f\u4e0b\u4e5f\u5f88\u597d\u7528\u3002<\/p>\n<h2>\u5e38\u89c4\u8f6e\u8be2<\/h2>\n<p>\u4ece\u670d\u52a1\u5668\u83b7\u53d6\u65b0\u4fe1\u606f\u7684\u6700\u7b80\u5355\u7684\u65b9\u5f0f\u662f\u5b9a\u671f\u8f6e\u8be2\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u5b9a\u671f\u5411\u670d\u52a1\u5668\u53d1\u51fa\u8bf7\u6c42\uff1a\u201c\u4f60\u597d\uff0c\u6211\u5728\u8fd9\u513f\uff0c\u4f60\u6709\u5173\u4e8e\u6211\u7684\u4efb\u4f55\u4fe1\u606f\u5417\uff1f\u201d\u4f8b\u5982\uff0c\u6bcf 10 \u79d2\u4e00\u6b21\u3002<br \/>\n\u4f5c\u4e3a\u54cd\u5e94\uff0c\u670d\u52a1\u5668\u9996\u5148\u901a\u77e5\u81ea\u5df1\uff0c\u5ba2\u6237\u7aef\u5904\u4e8e\u5728\u7ebf\u72b6\u6001\uff0c\u7136\u540e \u2014\u2014 \u53d1\u9001\u76ee\u524d\u4e3a\u6b62\u7684\u6d88\u606f\u5305\u3002<br \/>\n\u8fd9\u53ef\u884c\uff0c\u4f46\u662f\u4e5f\u6709\u4e9b\u7f3a\u70b9\uff1a<\/p>\n<ol>\n<li>\u6d88\u606f\u4f20\u9012\u7684\u5ef6\u8fdf\u6700\u591a\u4e3a 10 \u79d2\uff08\u4e24\u4e2a\u8bf7\u6c42\u4e4b\u95f4\uff09\u3002<\/li>\n<li>\u5373\u4f7f\u6ca1\u6709\u6d88\u606f\uff0c\u670d\u52a1\u5668\u4e5f\u4f1a\u6bcf\u9694 10 \u79d2\u88ab\u8bf7\u6c42\u8f70\u70b8\u4e00\u6b21\uff0c\u5373\u4f7f\u7528\u6237\u5207\u6362\u5230\u5176\u4ed6\u5730\u65b9\u6216\u8005\u5904\u4e8e\u4f11\u7720\u72b6\u6001\uff0c\u4e5f\u662f\u5982\u6b64\u3002\u5c31\u6027\u80fd\u800c\u8a00\uff0c\u8fd9\u662f\u4e00\u4e2a\u5f88\u5927\u7684\u8d1f\u62c5\u3002<br \/>\n\u56e0\u6b64\uff0c\u5982\u679c\u6211\u4eec\u8ba8\u8bba\u7684\u662f\u4e00\u4e2a\u975e\u5e38\u5c0f\u7684\u670d\u52a1\uff0c\u90a3\u4e48\u8fd9\u79cd\u65b9\u5f0f\u53ef\u80fd\u53ef\u884c\uff0c\u4f46\u603b\u7684\u6765\u8bf4\uff0c\u5b83\u9700\u8981\u6539\u8fdb\u3002<\/li>\n<\/ol>\n<h2>\u957f\u8f6e\u8be2<\/h2>\n<p>\u6240\u8c13\u201c\u957f\u8f6e\u8be2\u201d\u662f\u8f6e\u8be2\u670d\u52a1\u5668\u7684\u4e00\u79cd\u66f4\u597d\u7684\u65b9\u5f0f\u3002<br \/>\n\u5b83\u4e5f\u5f88\u5bb9\u6613\u5b9e\u73b0\uff0c\u5e76\u4e14\u53ef\u4ee5\u65e0\u5ef6\u8fdf\u5730\u4f20\u9012\u6d88\u606f\u3002<br \/>\n\u5176\u6d41\u7a0b\u4e3a\uff1a<\/p>\n<ol>\n<li>\u8bf7\u6c42\u53d1\u9001\u5230\u670d\u52a1\u5668\u3002<\/li>\n<li>\u670d\u52a1\u5668\u5728\u6709\u6d88\u606f\u4e4b\u524d\u4e0d\u4f1a\u5173\u95ed\u8fde\u63a5\u3002<\/li>\n<li>\u5f53\u6d88\u606f\u51fa\u73b0\u65f6 \u2014\u2014 \u670d\u52a1\u5668\u5c06\u5bf9\u5176\u8bf7\u6c42\u4f5c\u51fa\u54cd\u5e94\u3002<\/li>\n<li>\u6d4f\u89c8\u5668\u7acb\u5373\u53d1\u51fa\u4e00\u4e2a\u65b0\u7684\u8bf7\u6c42\u3002<br \/>\n\u5bf9\u4e8e\u6b64\u65b9\u6cd5\uff0c\u6d4f\u89c8\u5668\u53d1\u51fa\u4e00\u4e2a\u8bf7\u6c42\u5e76\u4e0e\u670d\u52a1\u5668\u4e4b\u95f4\u5efa\u7acb\u8d77\u4e00\u4e2a\u6302\u8d77\u7684\uff08pending\uff09\u8fde\u63a5\u7684\u60c5\u51b5\u662f\u6807\u51c6\u7684\u3002\u4ec5\u5728\u6709\u6d88\u606f\u88ab\u4f20\u9012\u65f6\uff0c\u624d\u4f1a\u91cd\u65b0\u5efa\u7acb\u8fde\u63a5\u3002<br \/>\n<div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240701125241-4.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  decoding=\"async\" data-original=\"https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240701125241-4.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"Pasted image 20240701125241.png\"><\/div><br \/>\n\u5982\u679c\u8fde\u63a5\u4e22\u5931\uff0c\u53ef\u80fd\u662f\u56e0\u4e3a\u7f51\u7edc\u9519\u8bef\uff0c\u6d4f\u89c8\u5668\u4f1a\u7acb\u5373\u53d1\u9001\u4e00\u4e2a\u65b0\u8bf7\u6c42\u3002<br \/>\n\u5b9e\u73b0\u957f\u8f6e\u8be2\u7684\u5ba2\u6237\u7aef\u00a0<code>subscribe<\/code>\u00a0\u51fd\u6570\u7684\u793a\u4f8b\u4ee3\u7801\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">async function subscribe() {\n  let response = await fetch(&quot;\/subscribe&quot;);\n\n  if (response.status == 502) {\n    \/\/ \u72b6\u6001 502 \u662f\u8fde\u63a5\u8d85\u65f6\u9519\u8bef\uff0c\n    \/\/ \u8fde\u63a5\u6302\u8d77\u65f6\u95f4\u8fc7\u957f\u65f6\u53ef\u80fd\u4f1a\u53d1\u751f\uff0c\n    \/\/ \u8fdc\u7a0b\u670d\u52a1\u5668\u6216\u4ee3\u7406\u4f1a\u5173\u95ed\u5b83\n    \/\/ \u8ba9\u6211\u4eec\u91cd\u65b0\u8fde\u63a5\n    await subscribe();\n  } else if (response.status != 200) {\n    \/\/ \u4e00\u4e2a error \u2014\u2014 \u8ba9\u6211\u4eec\u663e\u793a\u5b83\n    showMessage(response.statusText);\n    \/\/ \u4e00\u79d2\u540e\u91cd\u65b0\u8fde\u63a5\n    await new Promise(resolve =&gt; setTimeout(resolve, 1000));\n    await subscribe();\n  } else {\n    \/\/ \u83b7\u53d6\u5e76\u663e\u793a\u6d88\u606f\n    let message = await response.text();\n    showMessage(message);\n    \/\/ \u518d\u6b21\u8c03\u7528 subscribe() \u4ee5\u83b7\u53d6\u4e0b\u4e00\u6761\u6d88\u606f\n    await subscribe();\n  }\n}\n\nsubscribe();\n<\/code><\/pre>\n<p>\u6b63\u5982\u4f60\u6240\u770b\u5230\u7684\uff0c<code>subscribe<\/code>\u00a0\u51fd\u6570\u53d1\u8d77\u4e86\u4e00\u4e2a\u00a0<code>fetch<\/code>\uff0c\u7136\u540e\u7b49\u5f85\u54cd\u5e94\uff0c\u5904\u7406\u5b83\uff0c\u5e76\u518d\u6b21\u8c03\u7528\u81ea\u8eab\u3002<\/p>\n<blockquote>\n<p>\u670d\u52a1\u5668\u5e94\u8be5\u53ef\u4ee5\u5904\u7406\u8bb8\u591a\u6302\u8d77\u7684\u8fde\u63a5<br \/>\n\u670d\u52a1\u5668\u67b6\u6784\u5fc5\u987b\u80fd\u591f\u5904\u7406\u8bb8\u591a\u6302\u8d77\u7684\u8fde\u63a5\u3002<br \/>\n\u67d0\u4e9b\u670d\u52a1\u5668\u67b6\u6784\u662f\u6bcf\u4e2a\u8fde\u63a5\u5bf9\u5e94\u4e00\u4e2a\u8fdb\u7a0b\uff0c\u5bfc\u81f4\u8fdb\u7a0b\u6570\u548c\u8fde\u63a5\u6570\u4e00\u6837\u591a\uff0c\u800c\u6bcf\u4e2a\u8fdb\u7a0b\u90fd\u4f1a\u6d88\u8017\u76f8\u5f53\u591a\u7684\u5185\u5b58\u3002\u56e0\u6b64\uff0c\u8fc7\u591a\u7684\u8fde\u63a5\u4f1a\u6d88\u8017\u6389\u5168\u90e8\u5185\u5b58\u3002<br \/>\n\u4f7f\u7528\u50cf PHP \u548c Ruby \u8bed\u8a00\u7f16\u5199\u7684\u540e\u7aef\u7a0b\u5e8f\u4f1a\u7ecf\u5e38\u9047\u5230\u8fd9\u4e2a\u95ee\u9898\u3002<br \/>\n\u4f7f\u7528 Node.js \u7f16\u5199\u7684\u670d\u52a1\u7aef\u7a0b\u5e8f\u901a\u5e38\u4e0d\u4f1a\u51fa\u73b0\u6b64\u7c7b\u95ee\u9898\u3002<br \/>\n\u4e5f\u5c31\u662f\u8bf4\uff0c\u8fd9\u4e0d\u662f\u7f16\u7a0b\u8bed\u8a00\u7684\u95ee\u9898\u3002\u5927\u591a\u6570\u73b0\u4ee3\u7f16\u7a0b\u8bed\u8a00\uff0c\u5305\u62ec PHP \u548c Ruby\uff0c\u90fd\u5141\u8bb8\u5b9e\u73b0\u66f4\u9002\u5f53\u7684\u540e\u7aef\u7a0b\u5e8f\u3002\u53ea\u662f\u8bf7\u786e\u4fdd\u4f60\u7684\u670d\u52a1\u5668\u67b6\u6784\u5728\u540c\u65f6\u6709\u5f88\u591a\u8fde\u63a5\u7684\u60c5\u51b5\u4e0b\u80fd\u591f\u6b63\u5e38\u5de5\u4f5c\u3002<\/p>\n<\/blockquote>\n<h2>\u4f7f\u7528\u573a\u666f<\/h2>\n<p>\u5728\u6d88\u606f\u5f88\u5c11\u7684\u60c5\u51b5\u4e0b\uff0c\u957f\u8f6e\u8be2\u5f88\u6709\u6548\u3002<br \/>\n\u5982\u679c\u6d88\u606f\u6bd4\u8f83\u9891\u7e41\uff0c\u90a3\u4e48\u4e0a\u9762\u63cf\u7ed8\u7684\u8bf7\u6c42-\u63a5\u6536\uff08requesting-receiving\uff09\u6d88\u606f\u7684\u56fe\u8868\u5c31\u4f1a\u53d8\u6210\u952f\u72b6\u72b6\uff08saw-like\uff09\u3002<br \/>\n\u6bcf\u4e2a\u6d88\u606f\u90fd\u662f\u4e00\u4e2a\u5355\u72ec\u7684\u8bf7\u6c42\uff0c\u5e76\u5e26\u6709 header\uff0c\u8eab\u4efd\u9a8c\u8bc1\u5f00\u9500\uff08authentication overhead\uff09\u7b49\u3002<br \/>\n\u56e0\u6b64\uff0c\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u9996\u9009\u53e6\u4e00\u79cd\u65b9\u6cd5\uff0c\u4f8b\u5982\uff1a<a href=\"https:\/\/zh.javascript.info\/websocket\">Websocket<\/a>\u00a0\u6216\u00a0<a href=\"https:\/\/zh.javascript.info\/server-sent-events\">Server Sent Events<\/a>\u3002<\/p>\n<h1>WebSocket<\/h1>\n<p>\u5728\u00a0<a href=\"https:\/\/datatracker.ietf.org\/doc\/html\/rfc6455\">RFC 6455<\/a>\u00a0\u89c4\u8303\u4e2d\u63cf\u8ff0\u7684\u00a0<code>WebSocket<\/code>\u00a0\u534f\u8bae\uff0c\u63d0\u4f9b\u4e86\u4e00\u79cd\u5728\u6d4f\u89c8\u5668\u548c\u670d\u52a1\u5668\u4e4b\u95f4\u5efa\u7acb\u6301\u4e45\u8fde\u63a5\u6765\u4ea4\u6362\u6570\u636e\u7684\u65b9\u6cd5\u3002\u6570\u636e\u53ef\u4ee5\u4f5c\u4e3a\u201c\u6570\u636e\u5305\u201d\u5728\u4e24\u4e2a\u65b9\u5411\u4e0a\u4f20\u9012\uff0c\u800c\u65e0\u9700\u4e2d\u65ad\u8fde\u63a5\u4e5f\u65e0\u9700\u989d\u5916\u7684 HTTP \u8bf7\u6c42\u3002<br \/>\n\u5bf9\u4e8e\u9700\u8981\u8fde\u7eed\u6570\u636e\u4ea4\u6362\u7684\u670d\u52a1\uff0c\u4f8b\u5982\u7f51\u7edc\u6e38\u620f\uff0c\u5b9e\u65f6\u4ea4\u6613\u7cfb\u7edf\u7b49\uff0cWebSocket \u5c24\u5176\u6709\u7528\u3002<\/p>\n<h2>\u4e00\u4e2a\u7b80\u5355\u4f8b\u5b50<\/h2>\n<p>\u8981\u6253\u5f00\u4e00\u4e2a WebSocket \u8fde\u63a5\uff0c\u6211\u4eec\u9700\u8981\u5728 url \u4e2d\u4f7f\u7528\u7279\u6b8a\u7684\u534f\u8bae\u00a0<code>ws<\/code>\u00a0\u521b\u5efa\u00a0<code>new WebSocket<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">let socket = new WebSocket(&quot;ws:\/\/javascript.info&quot;);\n<\/code><\/pre>\n<p>\u540c\u6837\u4e5f\u6709\u4e00\u4e2a\u52a0\u5bc6\u7684\u00a0<code>wss:\/\/<\/code>\u00a0\u534f\u8bae\u3002\u7c7b\u4f3c\u4e8e WebSocket \u4e2d\u7684 HTTPS\u3002<\/p>\n<blockquote>\n<p>\u59cb\u7ec8\u4f7f\u7528\u00a0<code>wss:\/\/<\/code><br \/>\n<code>wss:\/\/<\/code>\u00a0\u534f\u8bae\u4e0d\u4ec5\u662f\u88ab\u52a0\u5bc6\u7684\uff0c\u800c\u4e14\u66f4\u53ef\u9760\u3002<br \/>\n\u56e0\u4e3a\u00a0<code>ws:\/\/<\/code>\u00a0\u6570\u636e\u4e0d\u662f\u52a0\u5bc6\u7684\uff0c\u5bf9\u4e8e\u4efb\u4f55\u4e2d\u95f4\u4eba\u6765\u8bf4\u5176\u6570\u636e\u90fd\u662f\u53ef\u89c1\u7684\u3002\u5e76\u4e14\uff0c\u65e7\u7684\u4ee3\u7406\u670d\u52a1\u5668\u4e0d\u4e86\u89e3 WebSocket\uff0c\u5b83\u4eec\u53ef\u80fd\u4f1a\u56e0\u4e3a\u770b\u5230\u201c\u5947\u602a\u7684\u201d header \u800c\u4e2d\u6b62\u8fde\u63a5\u3002<br \/>\n\u53e6\u4e00\u65b9\u9762\uff0c<code>wss:\/\/<\/code>\u00a0\u662f\u57fa\u4e8e TLS \u7684 WebSocket\uff0c\u7c7b\u4f3c\u4e8e HTTPS \u662f\u57fa\u4e8e TLS \u7684 HTTP\uff09\uff0c\u4f20\u8f93\u5b89\u5168\u5c42\u5728\u53d1\u9001\u65b9\u5bf9\u6570\u636e\u8fdb\u884c\u4e86\u52a0\u5bc6\uff0c\u5728\u63a5\u6536\u65b9\u8fdb\u884c\u89e3\u5bc6\u3002\u56e0\u6b64\uff0c\u6570\u636e\u5305\u662f\u901a\u8fc7\u4ee3\u7406\u52a0\u5bc6\u4f20\u8f93\u7684\u3002\u5b83\u4eec\u770b\u4e0d\u5230\u4f20\u8f93\u7684\u91cc\u9762\u7684\u5185\u5bb9\uff0c\u4e14\u4f1a\u8ba9\u8fd9\u4e9b\u6570\u636e\u901a\u8fc7\u3002<\/p>\n<\/blockquote>\n<p>\u4e00\u65e6 socket \u88ab\u5efa\u7acb\uff0c\u6211\u4eec\u5c31\u5e94\u8be5\u76d1\u542c socket \u4e0a\u7684\u4e8b\u4ef6\u3002\u4e00\u5171\u6709 4 \u4e2a\u4e8b\u4ef6\uff1a<\/p>\n<ul>\n<li><strong><code>open<\/code><\/strong>\u00a0\u2014\u2014 \u8fde\u63a5\u5df2\u5efa\u7acb\uff0c<\/li>\n<li><strong><code>message<\/code><\/strong>\u00a0\u2014\u2014 \u63a5\u6536\u5230\u6570\u636e\uff0c<\/li>\n<li><strong><code>error<\/code><\/strong>\u00a0\u2014\u2014 WebSocket \u9519\u8bef\uff0c<\/li>\n<li><strong><code>close<\/code><\/strong>\u00a0\u2014\u2014 \u8fde\u63a5\u5df2\u5173\u95ed\u3002<br \/>\n\u2026\u2026\u5982\u679c\u6211\u4eec\u60f3\u53d1\u9001\u4e00\u4e9b\u4e1c\u897f\uff0c\u90a3\u4e48\u53ef\u4ee5\u4f7f\u7528\u00a0<code>socket.send(data)<\/code>\u3002<br \/>\n\u8fd9\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let socket = new WebSocket(&quot;wss:\/\/javascript.info\/article\/websocket\/demo\/hello&quot;);\n\nsocket.onopen = function(e) {\n  alert(&quot;[open] Connection established&quot;);\n  alert(&quot;Sending to server&quot;);\n  socket.send(&quot;My name is John&quot;);\n};\n\nsocket.onmessage = function(event) {\n  alert(`[message] Data received from server: ${event.data}`);\n};\n\nsocket.onclose = function(event) {\n  if (event.wasClean) {\n    alert(`[close] Connection closed cleanly, code=${event.code} reason=${event.reason}`);\n  } else {\n    \/\/ \u4f8b\u5982\u670d\u52a1\u5668\u8fdb\u7a0b\u88ab\u6740\u6b7b\u6216\u7f51\u7edc\u4e2d\u65ad\n    \/\/ \u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0cevent.code \u901a\u5e38\u4e3a 1006\n    alert('[close] Connection died');\n  }\n};\n\nsocket.onerror = function(error) {\n  alert(`[error] ${error.message}`);\n};\n<\/code><\/pre>\n<p>\u5728\u4e0a\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u5047\u8bbe\u8fd0\u884c\u7740\u4e00\u4e2a\u7528 Node.js \u5199\u7684\u5c0f\u578b\u670d\u52a1\u5668\u00a0<a href=\"https:\/\/zh.javascript.info\/article\/websocket\/demo\/server.js\">server.js<\/a>\u3002\u5b83\u54cd\u5e94\u4e3a \u201cHello from server, John\u201d\uff0c\u7136\u540e\u7b49\u5f85 5 \u79d2\uff0c\u5173\u95ed\u8fde\u63a5\u3002<br \/>\n\u6240\u4ee5\u4e8b\u4ef6\u987a\u5e8f\u4e3a\uff1a<code>open<\/code>\u00a0\u2192\u00a0<code>message<\/code>\u00a0\u2192\u00a0<code>close<\/code>\u3002<br \/>\n\u8fd9\u5c31\u662f WebSocket\uff0c\u6211\u4eec\u5df2\u7ecf\u53ef\u4ee5\u4f7f\u7528 WebSocket \u901a\u4fe1\u4e86\u3002\u5f88\u7b80\u5355\uff0c\u4e0d\u662f\u5417\uff1f<br \/>\n\u73b0\u5728\u8ba9\u6211\u4eec\u66f4\u6df1\u5165\u5730\u5b66\u4e60\u5b83\u3002<\/p>\n<h2>\u5efa\u7acb WebSocket<\/h2>\n<p>\u5f53\u00a0<code>new WebSocket(url)<\/code>\u00a0\u88ab\u521b\u5efa\u540e\uff0c\u5b83\u5c06\u7acb\u5373\u5f00\u59cb\u8fde\u63a5\u3002<br \/>\n\u5728\u8fde\u63a5\u671f\u95f4\uff0c\u6d4f\u89c8\u5668\uff08\u4f7f\u7528 header\uff09\u95ee\u670d\u52a1\u5668\uff1a\u201c\u4f60\u652f\u6301 WebSocket \u5417\uff1f\u201d\u5982\u679c\u670d\u52a1\u5668\u56de\u590d\u8bf4\u201c\u6211\u652f\u6301\u201d\uff0c\u90a3\u4e48\u901a\u4fe1\u5c31\u4ee5 WebSocket \u534f\u8bae\u7ee7\u7eed\u8fdb\u884c\uff0c\u8be5\u534f\u8bae\u6839\u672c\u4e0d\u662f HTTP\u3002<br \/>\n<div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240701132637-4.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  decoding=\"async\" data-original=\"https:\/\/levin.ink\/wp-content\/uploads\/2024\/07\/Pasted-image-20240701132637-4.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"Pasted image 20240701132637.png\"><\/div><br \/>\n\u8fd9\u662f\u7531\u00a0<code>new WebSocket(&quot;wss:\/\/javascript.info\/chat&quot;)<\/code>\u00a0\u53d1\u51fa\u7684\u8bf7\u6c42\u7684\u6d4f\u89c8\u5668 header \u793a\u4f8b\u3002<\/p>\n<pre><code class=\"language-PlainText\">GET \/chat\nHost: javascript.info\nOrigin: https:\/\/javascript.info\nConnection: Upgrade\nUpgrade: websocket\nSec-WebSocket-Key: Iv8io\/9s+lYFgZWcXczP8Q==\nSec-WebSocket-Version: 13\n<\/code><\/pre>\n<ul>\n<li><code>Origin<\/code>\u00a0\u2014\u2014 \u5ba2\u6237\u7aef\u9875\u9762\u7684\u6e90\uff0c\u4f8b\u5982\u00a0<code>https:\/\/javascript.info<\/code>\u3002WebSocket \u5bf9\u8c61\u662f\u539f\u751f\u652f\u6301\u8de8\u6e90\u7684\u3002\u6ca1\u6709\u7279\u6b8a\u7684 header \u6216\u5176\u4ed6\u9650\u5236\u3002\u65e7\u7684\u670d\u52a1\u5668\u65e0\u6cd5\u5904\u7406 WebSocket\uff0c\u56e0\u6b64\u4e0d\u5b58\u5728\u517c\u5bb9\u6027\u95ee\u9898\u3002\u4f46\u00a0<code>Origin<\/code>\u00a0header \u5f88\u91cd\u8981\uff0c\u56e0\u4e3a\u5b83\u5141\u8bb8\u670d\u52a1\u5668\u51b3\u5b9a\u662f\u5426\u4f7f\u7528 WebSocket \u4e0e\u8be5\u7f51\u7ad9\u901a\u4fe1\u3002<\/li>\n<li><code>Connection: Upgrade<\/code>\u00a0\u2014\u2014 \u8868\u793a\u5ba2\u6237\u7aef\u60f3\u8981\u66f4\u6539\u534f\u8bae\u3002<\/li>\n<li><code>Upgrade: websocket<\/code>\u00a0\u2014\u2014 \u8bf7\u6c42\u7684\u534f\u8bae\u662f \u201cwebsocket\u201d\u3002<\/li>\n<li><code>Sec-WebSocket-Key<\/code>\u00a0\u2014\u2014 \u6d4f\u89c8\u5668\u968f\u673a\u751f\u6210\u7684\u5b89\u5168\u5bc6\u94a5\u3002<\/li>\n<li><code>Sec-WebSocket-Version<\/code>\u00a0\u2014\u2014 WebSocket \u534f\u8bae\u7248\u672c\uff0c\u5f53\u524d\u4e3a 13\u3002<\/li>\n<\/ul>\n<blockquote>\n<p>\u65e0\u6cd5\u6a21\u62df WebSocket \u63e1\u624b<br \/>\n\u6211\u4eec\u4e0d\u80fd\u4f7f\u7528\u00a0<code>XMLHttpRequest<\/code>\u00a0\u6216\u00a0<code>fetch<\/code>\u00a0\u6765\u8fdb\u884c\u8fd9\u79cd HTTP \u8bf7\u6c42\uff0c\u56e0\u4e3a\u4e0d\u5141\u8bb8 JavaScript \u8bbe\u7f6e\u8fd9\u4e9b header\u3002<\/p>\n<\/blockquote>\n<p>\u5982\u679c\u670d\u52a1\u5668\u540c\u610f\u5207\u6362\u4e3a WebSocket \u534f\u8bae\uff0c\u670d\u52a1\u5668\u5e94\u8be5\u8fd4\u56de\u54cd\u5e94\u7801 101\uff1a<\/p>\n<pre><code class=\"language-PlainText\">101 Switching Protocols\nUpgrade: websocket\nConnection: Upgrade\nSec-WebSocket-Accept: hsBlbuDTkk24srzEOTBUlZAlC2g=\n<\/code><\/pre>\n<p>\u8fd9\u91cc\u00a0<code>Sec-WebSocket-Accept<\/code>\u00a0\u662f\u00a0<code>Sec-WebSocket-Key<\/code>\uff0c\u662f\u4f7f\u7528\u7279\u6b8a\u7684\u7b97\u6cd5\u91cd\u65b0\u7f16\u7801\u7684\u3002\u6d4f\u89c8\u5668\u4f7f\u7528\u5b83\u6765\u786e\u4fdd\u54cd\u5e94\u4e0e\u8bf7\u6c42\u76f8\u5bf9\u5e94\u3002<br \/>\n\u7136\u540e\uff0c\u4f7f\u7528 WebSocket \u534f\u8bae\u4f20\u8f93\u6570\u636e\uff0c\u6211\u4eec\u5f88\u5feb\u5c31\u4f1a\u770b\u5230\u5b83\u7684\u7ed3\u6784\uff08\u201cframes\u201d\uff09\u3002\u5b83\u6839\u672c\u4e0d\u662f HTTP\u3002<\/p>\n<h3>\u6269\u5c55\u548c\u5b50\u534f\u8bae<\/h3>\n<p>WebSocket \u53ef\u80fd\u8fd8\u6709\u5176\u4ed6 header\uff0c<code>Sec-WebSocket-Extensions<\/code>\u00a0\u548c\u00a0<code>Sec-WebSocket-Protocol<\/code>\uff0c\u5b83\u4eec\u63cf\u8ff0\u4e86\u6269\u5c55\u548c\u5b50\u534f\u8bae\u3002<br \/>\n\u4f8b\u5982\uff1a<\/p>\n<ul>\n<li><code>Sec-WebSocket-Extensions: deflate-frame<\/code>\u00a0\u8868\u793a\u6d4f\u89c8\u5668\u652f\u6301\u6570\u636e\u538b\u7f29\u3002\u6269\u5c55\u4e0e\u4f20\u8f93\u6570\u636e\u6709\u5173\uff0c\u6269\u5c55\u4e86 WebSocket \u534f\u8bae\u7684\u529f\u80fd\u3002<code>Sec-WebSocket-Extensions<\/code>\u00a0header \u7531\u6d4f\u89c8\u5668\u81ea\u52a8\u53d1\u9001\uff0c\u5176\u4e2d\u5305\u542b\u5176\u652f\u6301\u7684\u6240\u6709\u6269\u5c55\u7684\u5217\u8868\u3002<\/li>\n<li><code>Sec-WebSocket-Protocol: soap, wamp<\/code>\u00a0\u8868\u793a\u6211\u4eec\u4e0d\u4ec5\u8981\u4f20\u8f93\u4efb\u4f55\u6570\u636e\uff0c\u8fd8\u8981\u4f20\u8f93\u00a0<a href=\"https:\/\/en.wikipedia.org\/wiki\/SOAP\">SOAP<\/a>\u00a0\u6216 WAMP\uff08\u201cThe WebSocket Application Messaging Protocol\u201d\uff09\u534f\u8bae\u4e2d\u7684\u6570\u636e\u3002WebSocket \u5b50\u534f\u8bae\u5df2\u7ecf\u5728\u00a0<a href=\"https:\/\/www.iana.org\/assignments\/websocket\/websocket.xml\">IANA catalogue<\/a>\u00a0\u4e2d\u6ce8\u518c\u3002\u56e0\u6b64\uff0c\u6b64 header \u63cf\u8ff0\u4e86\u6211\u4eec\u5c06\u8981\u4f7f\u7528\u7684\u6570\u636e\u683c\u5f0f\u3002<br \/>\n\u8fd9\u4e2a\u53ef\u9009\u7684 header \u662f\u4f7f\u7528\u00a0<code>new WebSocket<\/code>\u00a0\u7684\u7b2c\u4e8c\u4e2a\u53c2\u6570\u8bbe\u7f6e\u7684\u3002\u5b83\u662f\u5b50\u534f\u8bae\u6570\u7ec4\uff0c\u4f8b\u5982\uff0c\u5982\u679c\u6211\u4eec\u60f3\u4f7f\u7528 SOAP \u6216 WAMP\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let socket = new WebSocket(&quot;wss:\/\/javascript.info\/chat&quot;, [&quot;soap&quot;, &quot;wamp&quot;]);\n<\/code><\/pre>\n<p>\u670d\u52a1\u5668\u5e94\u8be5\u4f7f\u7528\u540c\u610f\u4f7f\u7528\u7684\u534f\u8bae\u548c\u6269\u5c55\u7684\u5217\u8868\u8fdb\u884c\u54cd\u5e94\u3002<br \/>\n\u4f8b\u5982\uff0c\u8fd9\u4e2a\u8bf7\u6c42\uff1a<\/p>\n<pre><code class=\"language-PlainText\">GET \/chat\nHost: javascript.info\nUpgrade: websocket\nConnection: Upgrade\nOrigin: https:\/\/javascript.info\nSec-WebSocket-Key: Iv8io\/9s+lYFgZWcXczP8Q==\nSec-WebSocket-Version: 13\nSec-WebSocket-Extensions: deflate-frame\nSec-WebSocket-Protocol: soap, wamp\n<\/code><\/pre>\n<p>\u54cd\u5e94\uff1a<\/p>\n<pre><code class=\"language-PlainText\">101 Switching Protocols\nUpgrade: websocket\nConnection: Upgrade\nSec-WebSocket-Accept: hsBlbuDTkk24srzEOTBUlZAlC2g=\nSec-WebSocket-Extensions: deflate-frame\nSec-WebSocket-Protocol: soap\n<\/code><\/pre>\n<p>\u5728\u8fd9\u91cc\u670d\u52a1\u5668\u54cd\u5e94 \u2014\u2014 \u5b83\u652f\u6301\u6269\u5c55 \u201cdeflate-frame\u201d\uff0c\u5e76\u4e14\u4ec5\u652f\u6301\u6240\u8bf7\u6c42\u7684\u5b50\u534f\u8bae\u4e2d\u7684 SOAP\u3002<\/p>\n<h2>\u6570\u636e\u4f20\u8f93<\/h2>\n<p>WebSocket \u901a\u4fe1\u7531 \u201cframes\u201d\uff08\u5373\u6570\u636e\u7247\u6bb5\uff09\u7ec4\u6210\uff0c\u53ef\u4ee5\u4ece\u4efb\u4f55\u4e00\u65b9\u53d1\u9001\uff0c\u5e76\u4e14\u6709\u4ee5\u4e0b\u51e0\u79cd\u7c7b\u578b\uff1a<\/p>\n<ul>\n<li>\u201ctext frames\u201d \u2014\u2014 \u5305\u542b\u5404\u65b9\u53d1\u9001\u7ed9\u5f7c\u6b64\u7684\u6587\u672c\u6570\u636e\u3002<\/li>\n<li>\u201cbinary data frames\u201d \u2014\u2014 \u5305\u542b\u5404\u65b9\u53d1\u9001\u7ed9\u5f7c\u6b64\u7684\u4e8c\u8fdb\u5236\u6570\u636e\u3002<\/li>\n<li>\u201cping\/pong frames\u201d \u88ab\u7528\u4e8e\u68c0\u67e5\u4ece\u670d\u52a1\u5668\u53d1\u9001\u7684\u8fde\u63a5\uff0c\u6d4f\u89c8\u5668\u4f1a\u81ea\u52a8\u54cd\u5e94\u5b83\u4eec\u3002<\/li>\n<li>\u8fd8\u6709 \u201cconnection close frame\u201d \u4ee5\u53ca\u5176\u4ed6\u670d\u52a1 frames\u3002<br \/>\n\u5728\u6d4f\u89c8\u5668\u91cc\uff0c\u6211\u4eec\u4ec5\u76f4\u63a5\u4f7f\u7528\u6587\u672c\u6216\u4e8c\u8fdb\u5236 frames\u3002<br \/>\n<strong>WebSocket\u00a0<code>.send()<\/code>\u00a0\u65b9\u6cd5\u53ef\u4ee5\u53d1\u9001\u6587\u672c\u6216\u4e8c\u8fdb\u5236\u6570\u636e\u3002<\/strong><br \/>\n<code>socket.send(body)<\/code>\u00a0\u8c03\u7528\u5141\u8bb8\u00a0<code>body<\/code>\u00a0\u662f\u5b57\u7b26\u4e32\u6216\u4e8c\u8fdb\u5236\u683c\u5f0f\uff0c\u5305\u62ec\u00a0<code>Blob<\/code>\uff0c<code>ArrayBuffer<\/code>\u00a0\u7b49\u3002\u4e0d\u9700\u8981\u989d\u5916\u7684\u8bbe\u7f6e\uff1a\u76f4\u63a5\u53d1\u9001\u5b83\u4eec\u5c31\u53ef\u4ee5\u4e86\u3002<br \/>\n<strong>\u5f53\u6211\u4eec\u6536\u5230\u6570\u636e\u65f6\uff0c\u6587\u672c\u603b\u662f\u4ee5\u5b57\u7b26\u4e32\u5f62\u5f0f\u5448\u73b0\u3002\u800c\u5bf9\u4e8e\u4e8c\u8fdb\u5236\u6570\u636e\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u00a0<code>Blob<\/code>\u00a0\u548c\u00a0<code>ArrayBuffer<\/code>\u00a0\u683c\u5f0f\u4e4b\u95f4\u8fdb\u884c\u9009\u62e9\u3002<\/strong><br \/>\n\u5b83\u662f\u7531\u00a0<code>socket.binaryType<\/code>\u00a0\u5c5e\u6027\u8bbe\u7f6e\u7684\uff0c\u9ed8\u8ba4\u4e3a\u00a0<code>&quot;blob&quot;<\/code>\uff0c\u56e0\u6b64\u4e8c\u8fdb\u5236\u6570\u636e\u901a\u5e38\u4ee5\u00a0<code>Blob<\/code>\u00a0\u5bf9\u8c61\u5448\u73b0\u3002<br \/>\n<a href=\"https:\/\/zh.javascript.info\/blob\">Blob<\/a>\u00a0\u662f\u9ad8\u7ea7\u7684\u4e8c\u8fdb\u5236\u5bf9\u8c61\uff0c\u5b83\u76f4\u63a5\u4e0e\u00a0<code>&lt;a&gt;<\/code>\uff0c<code>&lt;img&gt;<\/code>\u00a0\u53ca\u5176\u4ed6\u6807\u7b7e\u96c6\u6210\u5728\u4e00\u8d77\uff0c\u56e0\u6b64\uff0c\u9ed8\u8ba4\u4ee5\u00a0<code>Blob<\/code>\u00a0\u683c\u5f0f\u662f\u4e00\u4e2a\u660e\u667a\u7684\u9009\u62e9\u3002\u4f46\u662f\u5bf9\u4e8e\u4e8c\u8fdb\u5236\u5904\u7406\uff0c\u8981\u8bbf\u95ee\u5355\u4e2a\u6570\u636e\u5b57\u8282\uff0c\u6211\u4eec\u53ef\u4ee5\u5c06\u5176\u6539\u4e3a\u00a0<code>&quot;arraybuffer&quot;<\/code>\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">socket.binaryType = &quot;arraybuffer&quot;;\nsocket.onmessage = (event) =&gt; {\n  \/\/ event.data \u53ef\u4ee5\u662f\u6587\u672c\uff08\u5982\u679c\u662f\u6587\u672c\uff09\uff0c\u4e5f\u53ef\u4ee5\u662f arraybuffer\uff08\u5982\u679c\u662f\u4e8c\u8fdb\u5236\u6570\u636e\uff09\n};\n<\/code><\/pre>\n<h2>\u9650\u901f<\/h2>\n<p>\u60f3\u8c61\u4e00\u4e0b\uff1a\u6211\u4eec\u7684\u5e94\u7528\u7a0b\u5e8f\u6b63\u5728\u751f\u6210\u5927\u91cf\u8981\u53d1\u9001\u7684\u6570\u636e\u3002\u4f46\u662f\u7528\u6237\u7684\u7f51\u901f\u5374\u5f88\u6162\uff0c\u53ef\u80fd\u662f\u5728\u4e61\u4e0b\u7684\u79fb\u52a8\u8bbe\u5907\u4e0a\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u53cd\u590d\u5730\u8c03\u7528\u00a0<code>socket.send(data)<\/code>\u3002\u4f46\u662f\u6570\u636e\u5c06\u4f1a\u7f13\u51b2\uff08\u50a8\u5b58\uff09\u5728\u5185\u5b58\u4e2d\uff0c\u5e76\u4e14\u53ea\u80fd\u5728\u7f51\u901f\u5141\u8bb8\u7684\u60c5\u51b5\u4e0b\u5c3d\u5feb\u5c06\u6570\u636e\u53d1\u9001\u51fa\u53bb\u3002<br \/>\n<code>socket.bufferedAmount<\/code>\u00a0\u5c5e\u6027\u50a8\u5b58\u4e86\u76ee\u524d\u5df2\u7f13\u51b2\u7684\u5b57\u8282\u6570\uff0c\u7b49\u5f85\u901a\u8fc7\u7f51\u7edc\u53d1\u9001\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u68c0\u67e5\u5b83\u4ee5\u67e5\u770b socket \u662f\u5426\u771f\u7684\u53ef\u7528\u4e8e\u4f20\u8f93\u3002<\/p>\n<pre><code class=\"language-js\">\/\/ \u6bcf 100ms \u68c0\u67e5\u4e00\u6b21 socket\n\/\/ \u4ec5\u5f53\u6240\u6709\u73b0\u6709\u7684\u6570\u636e\u90fd\u5df2\u88ab\u53d1\u9001\u51fa\u53bb\u65f6\uff0c\u518d\u53d1\u9001\u66f4\u591a\u6570\u636e\nsetInterval(() =&gt; {\n  if (socket.bufferedAmount == 0) {\n    socket.send(moreData());\n  }\n}, 100);\n<\/code><\/pre>\n<h2>\u8fde\u63a5\u5173\u95ed<\/h2>\n<p>\u901a\u5e38\uff0c\u5f53\u4e00\u65b9\u60f3\u8981\u5173\u95ed\u8fde\u63a5\u65f6\uff08\u6d4f\u89c8\u5668\u548c\u670d\u52a1\u5668\u90fd\u5177\u6709\u76f8\u540c\u7684\u6743\u9650\uff09\uff0c\u5b83\u4eec\u4f1a\u53d1\u9001\u4e00\u4e2a\u5e26\u6709\u6570\u5b57\u7801\uff08numeric code\uff09\u548c\u6587\u672c\u5f62\u5f0f\u7684\u539f\u56e0\u7684 \u201cconnection close frame\u201d\u3002<br \/>\n\u5b83\u7684\u65b9\u6cd5\u662f\uff1a<\/p>\n<pre><code class=\"language-js\">socket.close([code], [reason]);\n<\/code><\/pre>\n<ul>\n<li><code>code<\/code>\u00a0\u662f\u4e00\u4e2a\u7279\u6b8a\u7684 WebSocket \u5173\u95ed\u7801\uff08\u53ef\u9009\uff09<\/li>\n<li><code>reason<\/code>\u00a0\u662f\u4e00\u4e2a\u63cf\u8ff0\u5173\u95ed\u539f\u56e0\u7684\u5b57\u7b26\u4e32\uff08\u53ef\u9009\uff09<br \/>\n\u7136\u540e\uff0c\u53e6\u5916\u4e00\u65b9\u901a\u8fc7\u00a0<code>close<\/code>\u00a0\u4e8b\u4ef6\u5904\u7406\u5668\u83b7\u53d6\u4e86\u5173\u95ed\u7801\u548c\u5173\u95ed\u539f\u56e0\uff0c\u4f8b\u5982\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">\/\/ \u5173\u95ed\u65b9\uff1a\nsocket.close(1000, &quot;Work complete&quot;);\n\n\/\/ \u53e6\u4e00\u65b9\nsocket.onclose = event =&gt; {\n  \/\/ event.code === 1000\n  \/\/ event.reason === &quot;Work complete&quot;\n  \/\/ event.wasClean === true (clean close)\n};\n<\/code><\/pre>\n<p>\u6700\u5e38\u89c1\u7684\u6570\u5b57\u7801\uff1a<\/p>\n<ul>\n<li><code>1000<\/code>\u00a0\u2014\u2014 \u9ed8\u8ba4\uff0c\u6b63\u5e38\u5173\u95ed\uff08\u5982\u679c\u6ca1\u6709\u6307\u660e\u00a0<code>code<\/code>\u00a0\u65f6\u4f7f\u7528\u5b83\uff09\uff0c<\/li>\n<li><code>1006<\/code>\u00a0\u2014\u2014 \u6ca1\u6709\u529e\u6cd5\u624b\u52a8\u8bbe\u5b9a\u8fd9\u4e2a\u6570\u5b57\u7801\uff0c\u8868\u793a\u8fde\u63a5\u4e22\u5931\uff08\u6ca1\u6709 close frame\uff09\u3002<br \/>\n\u8fd8\u6709\u5176\u4ed6\u6570\u5b57\u7801\uff0c\u4f8b\u5982\uff1a<\/li>\n<li><code>1001<\/code>\u00a0\u2014\u2014 \u4e00\u65b9\u6b63\u5728\u79bb\u5f00\uff0c\u4f8b\u5982\u670d\u52a1\u5668\u6b63\u5728\u5173\u95ed\uff0c\u6216\u8005\u6d4f\u89c8\u5668\u79bb\u5f00\u4e86\u8be5\u9875\u9762\uff0c<\/li>\n<li><code>1009<\/code>\u00a0\u2014\u2014 \u6d88\u606f\u592a\u5927\uff0c\u65e0\u6cd5\u5904\u7406\uff0c<\/li>\n<li><code>1011<\/code>\u00a0\u2014\u2014 \u670d\u52a1\u5668\u4e0a\u53d1\u751f\u610f\u5916\u9519\u8bef\uff0c<\/li>\n<li>\u2026\u2026\u7b49\u3002<br \/>\n\u5b8c\u6574\u5217\u8868\u8bf7\u89c1\u00a0<a href=\"https:\/\/tools.ietf.org\/html\/rfc6455#section-7.4.1\">RFC6455, \u00a77.4.1<\/a>\u3002<br \/>\nWebSocket \u7801\u6709\u70b9\u50cf HTTP \u7801\uff0c\u4f46\u5b83\u4eec\u662f\u4e0d\u540c\u7684\u3002\u7279\u522b\u662f\uff0c\u5c0f\u4e8e\u00a0<code>1000<\/code>\u00a0\u7684\u7801\u90fd\u662f\u88ab\u4fdd\u7559\u7684\uff0c\u5982\u679c\u6211\u4eec\u5c1d\u8bd5\u8bbe\u7f6e\u8fd9\u6837\u7684\u7801\uff0c\u5c06\u4f1a\u51fa\u73b0\u9519\u8bef\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-js\">\/\/ \u5728\u8fde\u63a5\u65ad\u5f00\u7684\u60c5\u51b5\u4e0b\nsocket.onclose = event =&gt; {\n  \/\/ event.code === 1006\n  \/\/ event.reason === &quot;&quot;\n  \/\/ event.wasClean === false\uff08\u672a\u5173\u95ed frame\uff09\n};\n<\/code><\/pre>\n<h2>\u8fde\u63a5\u72b6\u6001<\/h2>\n<p>\u8981\u83b7\u53d6\u8fde\u63a5\u72b6\u6001\uff0c\u53ef\u4ee5\u901a\u8fc7\u5e26\u6709\u503c\u7684\u00a0<code>socket.readyState<\/code>\u00a0\u5c5e\u6027\uff1a<\/p>\n<ul>\n<li><strong><code>0<\/code><\/strong>\u00a0\u2014\u2014 \u201cCONNECTING\u201d\uff1a\u8fde\u63a5\u8fd8\u672a\u5efa\u7acb\uff0c<\/li>\n<li><strong><code>1<\/code><\/strong>\u00a0\u2014\u2014 \u201cOPEN\u201d\uff1a\u901a\u4fe1\u4e2d\uff0c<\/li>\n<li><strong><code>2<\/code><\/strong>\u00a0\u2014\u2014 \u201cCLOSING\u201d\uff1a\u8fde\u63a5\u5173\u95ed\u4e2d\uff0c<\/li>\n<li><strong><code>3<\/code><\/strong>\u00a0\u2014\u2014 \u201cCLOSED\u201d\uff1a\u8fde\u63a5\u5df2\u5173\u95ed\u3002<\/li>\n<\/ul>\n<h2>\u804a\u5929\u793a\u4f8b<\/h2>\n<p>\u8ba9\u6211\u4eec\u6765\u770b\u4e00\u4e2a\u4f7f\u7528\u6d4f\u89c8\u5668 WebSocket API \u548c Node.js \u7684 WebSocket \u6a21\u5757\u00a0<a href=\"https:\/\/github.com\/websockets\/ws\">https:\/\/github.com\/websockets\/ws<\/a>\u00a0\u7684\u804a\u5929\u793a\u4f8b\u3002\u6211\u4eec\u5c06\u4e3b\u8981\u7cbe\u529b\u653e\u5728\u5ba2\u6237\u7aef\u4e0a\uff0c\u4f46\u662f\u670d\u52a1\u7aef\u4e5f\u5f88\u7b80\u5355\u3002<br \/>\nHTML\uff1a\u6211\u4eec\u9700\u8981\u4e00\u4e2a\u00a0<code>&lt;form&gt;<\/code>\u00a0\u6765\u53d1\u9001\u6d88\u606f\uff0c\u5e76\u4e14\u9700\u8981\u4e00\u4e2a\u00a0<code>&lt;div&gt;<\/code>\u00a0\u6765\u63a5\u6536\u6d88\u606f\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;!-- \u6d88\u606f\u8868\u5355 --&gt;\n&lt;form name=&quot;publish&quot;&gt;\n  &lt;input type=&quot;text&quot; name=&quot;message&quot;&gt;\n  &lt;input type=&quot;submit&quot; value=&quot;Send&quot;&gt;\n&lt;\/form&gt;\n\n&lt;!-- \u5e26\u6709\u6d88\u606f\u7684 div --&gt;\n&lt;div id=&quot;messages&quot;&gt;&lt;\/div&gt;\n<\/code><\/pre>\n<p>\u5728 JavaScript \u4e2d\uff0c\u6211\u4eec\u60f3\u8981\u505a\u4e09\u4ef6\u4e8b\uff1a<\/p>\n<ol>\n<li>\u6253\u5f00\u8fde\u63a5\u3002<\/li>\n<li>\u5728\u8868\u5355\u63d0\u4ea4\u4e2d \u2014\u2014\u00a0<code>socket.send(message)<\/code>\u00a0\u7528\u4e8e\u6d88\u606f\u3002<\/li>\n<li>\u5bf9\u4e8e\u4f20\u5165\u7684\u6d88\u606f \u2014\u2014 \u5c06\u5176\u9644\u52a0\uff08append\uff09\u5230\u00a0<code>div#messages<\/code>\u00a0\u4e0a\u3002<br \/>\n\u4ee3\u7801\u5982\u4e0b<\/li>\n<\/ol>\n<pre><code class=\"language-js\">let socket = new WebSocket(&quot;wss:\/\/javascript.info\/article\/websocket\/chat\/ws&quot;);\n\n\/\/ \u4ece\u8868\u5355\u53d1\u9001\u6d88\u606f\ndocument.forms.publish.onsubmit = function() {\n  let outgoingMessage = this.message.value;\n\n  socket.send(outgoingMessage);\n  return false;\n};\n\n\/\/ \u6536\u5230\u6d88\u606f \u2014\u2014 \u5728 div#messages \u4e2d\u663e\u793a\u6d88\u606f\nsocket.onmessage = function(event) {\n  let message = event.data;\n\n  let messageElem = document.createElement('div');\n  messageElem.textContent = message;\n  document.getElementById('messages').prepend(messageElem);\n}\n<\/code><\/pre>\n<p>\u670d\u52a1\u7aef\u4ee3\u7801\u6709\u70b9\u8d85\u51fa\u6211\u4eec\u7684\u8303\u56f4\u3002\u5728\u8fd9\u91cc\uff0c\u6211\u4eec\u5c06\u4f7f\u7528 Node.js\uff0c\u4f46\u4f60\u4e0d\u5fc5\u8fd9\u6837\u505a\u3002\u5176\u4ed6\u5e73\u53f0\u4e5f\u6709\u4f7f\u7528 WebSocket \u7684\u65b9\u6cd5\u3002<br \/>\n\u670d\u52a1\u5668\u7aef\u7684\u7b97\u6cd5\u4e3a\uff1a<\/p>\n<ol>\n<li>\u521b\u5efa\u00a0<code>clients = new Set()<\/code>\u00a0\u2014\u2014 \u4e00\u7cfb\u5217 socket\u3002<\/li>\n<li>\u5bf9\u4e8e\u6bcf\u4e2a\u88ab\u63a5\u53d7\u7684 WebSocket\uff0c\u5c06\u5176\u6dfb\u52a0\u5230\u00a0<code>clients.add(socket)<\/code>\uff0c\u5e76\u4e3a\u5176\u8bbe\u7f6e\u00a0<code>message<\/code>\u00a0\u4e8b\u4ef6\u4fa6\u542c\u5668\u4ee5\u83b7\u53d6\u5176\u6d88\u606f\u3002<\/li>\n<li>\u5f53\u63a5\u6536\u5230\u6d88\u606f\uff1a\u904d\u5386\u5ba2\u6237\u7aef\uff0c\u5e76\u5c06\u6d88\u606f\u53d1\u9001\u7ed9\u6240\u6709\u4eba\u3002<\/li>\n<li>\u5f53\u8fde\u63a5\u88ab\u5173\u95ed\uff1a<code>clients.delete(socket)<\/code>\u3002<\/li>\n<\/ol>\n<pre><code class=\"language-js\">const ws = new require('ws');\nconst wss = new ws.Server({noServer: true});\n\nconst clients = new Set();\n\nhttp.createServer((req, res) =&gt; {\n  \/\/ \u5728\u8fd9\u91cc\uff0c\u6211\u4eec\u4ec5\u5904\u7406 WebSocket \u8fde\u63a5\n  \/\/ \u5728\u5b9e\u9645\u9879\u76ee\u4e2d\uff0c\u6211\u4eec\u5728\u8fd9\u91cc\u8fd8\u4f1a\u6709\u5176\u4ed6\u4ee3\u7801\uff0c\u6765\u5904\u7406\u975e WebSocket \u8bf7\u6c42\n  wss.handleUpgrade(req, req.socket, Buffer.alloc(0), onSocketConnect);\n});\n\nfunction onSocketConnect(ws) {\n  clients.add(ws);\n\n  ws.on('message', function(message) {\n    message = message.slice(0, 50); \/\/ message \u7684\u6700\u5927\u957f\u5ea6\u4e3a 50\n\n    for(let client of clients) {\n      client.send(message);\n    }\n  });\n\n  ws.on('close', function() {\n    clients.delete(ws);\n  });\n}\n<\/code><\/pre>\n<h1>Server Sent Events<\/h1>\n<p><a href=\"https:\/\/html.spec.whatwg.org\/multipage\/comms.html#the-eventsource-interface\">Server-Sent Events<\/a>\u00a0\u89c4\u8303\u63cf\u8ff0\u4e86\u4e00\u4e2a\u5185\u5efa\u7684\u7c7b\u00a0<code>EventSource<\/code>\uff0c\u5b83\u80fd\u4fdd\u6301\u4e0e\u670d\u52a1\u5668\u7684\u8fde\u63a5\uff0c\u5e76\u5141\u8bb8\u4ece\u4e2d\u63a5\u6536\u4e8b\u4ef6\u3002<br \/>\n\u4e0e\u00a0<code>WebSocket<\/code>\u00a0\u7c7b\u4f3c\uff0c\u5176\u8fde\u63a5\u662f\u6301\u4e45\u7684\u3002<br \/>\n\u4f46\u662f\u4e24\u8005\u4e4b\u95f4\u6709\u51e0\u4e2a\u91cd\u8981\u7684\u533a\u522b\uff1a<\/p>\n<table>\n<thead>\n<tr>\n<th><code>WebSocket<\/code><\/th>\n<th><code>EventSource<\/code><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u53cc\u5411\uff1a\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u90fd\u80fd\u4ea4\u6362\u6d88\u606f<\/td>\n<td>\u5355\u5411\uff1a\u4ec5\u670d\u52a1\u7aef\u80fd\u53d1\u9001\u6d88\u606f<\/td>\n<\/tr>\n<tr>\n<td>\u4e8c\u8fdb\u5236\u548c\u6587\u672c\u6570\u636e<\/td>\n<td>\u4ec5\u6587\u672c\u6570\u636e<\/td>\n<\/tr>\n<tr>\n<td>WebSocket \u534f\u8bae<\/td>\n<td>\u5e38\u89c4 HTTP \u534f\u8bae<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u4e0e\u00a0<code>WebSocket<\/code>\u00a0\u76f8\u6bd4\uff0c<code>EventSource<\/code>\u00a0\u662f\u4e0e\u670d\u52a1\u5668\u901a\u4fe1\u7684\u4e00\u79cd\u4e0d\u90a3\u4e48\u5f3a\u5927\u7684\u65b9\u5f0f\u3002<br \/>\n\u6211\u4eec\u4e3a\u4ec0\u4e48\u8981\u4f7f\u7528\u5b83\uff1f<br \/>\n\u4e3b\u8981\u539f\u56e0\uff1a\u7b80\u5355\u3002\u5728\u5f88\u591a\u5e94\u7528\u4e2d\uff0c<code>WebSocket<\/code>\u00a0\u6709\u70b9\u5927\u6750\u5c0f\u7528\u3002<br \/>\n\u6211\u4eec\u9700\u8981\u4ece\u670d\u52a1\u5668\u63a5\u6536\u4e00\u4e2a\u6570\u636e\u6d41\uff1a\u53ef\u80fd\u662f\u804a\u5929\u6d88\u606f\u6216\u8005\u5e02\u573a\u4ef7\u683c\u7b49\u3002\u8fd9\u6b63\u662f\u00a0<code>EventSource<\/code>\u00a0\u6240\u64c5\u957f\u7684\u3002\u5b83\u8fd8\u652f\u6301\u81ea\u52a8\u91cd\u65b0\u8fde\u63a5\uff0c\u800c\u5728\u00a0<code>WebSocket<\/code>\u00a0\u4e2d\u8fd9\u4e2a\u529f\u80fd\u9700\u8981\u6211\u4eec\u624b\u52a8\u5b9e\u73b0\u3002\u6b64\u5916\uff0c\u5b83\u662f\u4e00\u4e2a\u666e\u901a\u7684\u65e7\u7684 HTTP\uff0c\u4e0d\u662f\u4e00\u4e2a\u65b0\u534f\u8bae\u3002<\/p>\n<h2>\u83b7\u53d6\u6d88\u606f<\/h2>\n<p>\u8981\u5f00\u59cb\u63a5\u6536\u6d88\u606f\uff0c\u6211\u4eec\u53ea\u9700\u8981\u521b\u5efa\u00a0<code>new EventSource(url)<\/code>\u00a0\u5373\u53ef\u3002<br \/>\n\u6d4f\u89c8\u5668\u5c06\u4f1a\u8fde\u63a5\u5230\u00a0<code>url<\/code>\u00a0\u5e76\u4fdd\u6301\u8fde\u63a5\u6253\u5f00\uff0c\u7b49\u5f85\u4e8b\u4ef6\u3002<br \/>\n\u670d\u52a1\u5668\u54cd\u5e94\u72b6\u6001\u7801\u5e94\u8be5\u4e3a 200\uff0cheader \u4e3a\u00a0<code>Content-Type: text\/event-stream<\/code>\uff0c\u7136\u540e\u4fdd\u6301\u6b64\u8fde\u63a5\u5e76\u4ee5\u4e00\u79cd\u7279\u6b8a\u7684\u683c\u5f0f\u5199\u5165\u6d88\u606f\uff0c\u5c31\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-Text\">data: Message 1\n\ndata: Message 2\n\ndata: Message 3\ndata: of two lines\n<\/code><\/pre>\n<ul>\n<li><code>data:<\/code>\u00a0\u540e\u4e3a\u6d88\u606f\u6587\u672c\uff0c\u5192\u53f7\u540e\u9762\u7684\u7a7a\u683c\u662f\u53ef\u9009\u7684\u3002<\/li>\n<li>\u6d88\u606f\u4ee5\u53cc\u6362\u884c\u7b26\u00a0<code>\\n\\n<\/code>\u00a0\u5206\u9694\u3002<\/li>\n<li>\u8981\u53d1\u9001\u4e00\u4e2a\u6362\u884c\u00a0<code>\\n<\/code>\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u8981\u6362\u884c\u7684\u4f4d\u7f6e\u7acb\u5373\u518d\u53d1\u9001\u4e00\u4e2a\u00a0<code>data:<\/code>\uff08\u4e0a\u9762\u7684\u7b2c\u4e09\u6761\u6d88\u606f\uff09\u3002<br \/>\n\u5728\u5b9e\u9645\u5f00\u53d1\u4e2d\uff0c\u590d\u6742\u7684\u6d88\u606f\u901a\u5e38\u662f\u7528 JSON \u7f16\u7801\u540e\u53d1\u9001\u3002\u6362\u884c\u7b26\u5728\u5176\u4e2d\u7f16\u7801\u4e3a\u00a0<code>\\n<\/code>\uff0c\u56e0\u6b64\u4e0d\u9700\u8981\u591a\u884c\u00a0<code>data:<\/code>\u00a0\u6d88\u606f\u3002<br \/>\n\u4f8b\u5982\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">data: {&quot;user&quot;:&quot;John&quot;,&quot;message&quot;:&quot;First line\\n Second line&quot;}\n<\/code><\/pre>\n<p>\u2026\u2026\u56e0\u6b64\uff0c\u6211\u4eec\u53ef\u4ee5\u5047\u8bbe\u4e00\u4e2a\u00a0<code>data:<\/code>\u00a0\u53ea\u4fdd\u5b58\u4e86\u4e00\u6761\u6d88\u606f\u3002<br \/>\n\u5bf9\u4e8e\u6bcf\u4e2a\u8fd9\u6837\u7684\u6d88\u606f\uff0c\u90fd\u4f1a\u751f\u6210\u00a0<code>message<\/code>\u00a0\u4e8b\u4ef6\uff1a<\/p>\n<pre><code class=\"language-js\">let eventSource = new EventSource(&quot;\/events\/subscribe&quot;);\n\neventSource.onmessage = function(event) {\n  console.log(&quot;New message&quot;, event.data);\n  \/\/ \u5bf9\u4e8e\u4e0a\u9762\u7684\u6570\u636e\u6d41\u5c06\u6253\u5370\u4e09\u6b21\n};\n\n\/\/ \u6216 eventSource.addEventListener('message', ...)\n<\/code><\/pre>\n<h3>\u8de8\u6e90\u8bf7\u6c42<\/h3>\n<p><code>EventSource<\/code>\u00a0\u652f\u6301\u8de8\u6e90\u8bf7\u6c42\uff0c\u5c31\u50cf\u00a0<code>fetch<\/code>\u00a0\u548c\u4efb\u4f55\u5176\u4ed6\u7f51\u7edc\u65b9\u6cd5\u3002\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4efb\u4f55 URL\uff1a<\/p>\n<pre><code class=\"language-js\">let source = new EventSource(&quot;https:\/\/another-site.com\/events&quot;);\n<\/code><\/pre>\n<p>\u8fdc\u7a0b\u670d\u52a1\u5668\u5c06\u4f1a\u83b7\u53d6\u5230\u00a0<code>Origin<\/code>\u00a0header\uff0c\u5e76\u4e14\u5fc5\u987b\u4ee5\u00a0<code>Access-Control-Allow-Origin<\/code>\u00a0\u54cd\u5e94\u6765\u5904\u7406\u3002<br \/>\n\u8981\u4f20\u9012\u51ed\u8bc1\uff08credentials\uff09\uff0c\u6211\u4eec\u5e94\u8be5\u8bbe\u7f6e\u9644\u52a0\u9009\u9879\u00a0<code>withCredentials<\/code>\uff0c\u5c31\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">let source = new EventSource(&quot;https:\/\/another-site.com\/events&quot;, {\n  withCredentials: true\n});\n<\/code><\/pre>\n<p>\u66f4\u591a\u5173\u4e8e\u8de8\u6e90 header \u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u8bf7\u53c2\u89c1\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">Fetch\uff1a\u8de8\u6e90\u8bf7\u6c42<\/a>\u3002<\/p>\n<h2>\u91cd\u65b0\u8fde\u63a5<\/h2>\n<p>\u521b\u5efa\u4e4b\u540e\uff0c<code>new EventSource<\/code>\u00a0\u8fde\u63a5\u5230\u670d\u52a1\u5668\uff0c\u5982\u679c\u8fde\u63a5\u65ad\u5f00 \u2014\u2014 \u5219\u91cd\u65b0\u8fde\u63a5\u3002<br \/>\n\u8fd9\u975e\u5e38\u65b9\u4fbf\uff0c\u6211\u4eec\u4e0d\u7528\u53bb\u5173\u5fc3\u91cd\u65b0\u8fde\u63a5\u7684\u4e8b\u60c5\u3002<br \/>\n\u6bcf\u6b21\u91cd\u65b0\u8fde\u63a5\u4e4b\u95f4\u6709\u4e00\u70b9\u5c0f\u7684\u5ef6\u8fdf\uff0c\u9ed8\u8ba4\u4e3a\u51e0\u79d2\u949f\u3002<br \/>\n\u670d\u52a1\u5668\u53ef\u4ee5\u4f7f\u7528\u00a0<code>retry:<\/code>\u00a0\u6765\u8bbe\u7f6e\u9700\u8981\u7684\u5ef6\u8fdf\u54cd\u5e94\u65f6\u95f4\uff08\u4ee5\u6beb\u79d2\u4e3a\u5355\u4f4d\uff09\u3002<\/p>\n<pre><code class=\"language-Text\">retry: 15000\ndata: Hello, I set the reconnection delay to 15 seconds\n<\/code><\/pre>\n<p><code>retry:<\/code>\u00a0\u65e2\u53ef\u4ee5\u4e0e\u67d0\u4e9b\u6570\u636e\u4e00\u8d77\u51fa\u73b0\uff0c\u4e5f\u53ef\u4ee5\u4f5c\u4e3a\u72ec\u7acb\u7684\u6d88\u606f\u51fa\u73b0\u3002<br \/>\n\u5728\u91cd\u65b0\u8fde\u63a5\u4e4b\u524d\uff0c\u6d4f\u89c8\u5668\u9700\u8981\u7b49\u5f85\u90a3\u4e48\u591a\u6beb\u79d2\u3002\u751a\u81f3\u66f4\u957f\uff0c\u4f8b\u5982\uff0c\u5982\u679c\u6d4f\u89c8\u5668\u77e5\u9053\uff08\u4ece\u64cd\u4f5c\u7cfb\u7edf\uff09\u6b64\u65f6\u6ca1\u6709\u7f51\u7edc\u8fde\u63a5\uff0c\u5b83\u4f1a\u7b49\u5230\u8fde\u63a5\u51fa\u73b0\uff0c\u7136\u540e\u91cd\u8bd5\u3002<\/p>\n<ul>\n<li>\u5982\u679c\u670d\u52a1\u5668\u60f3\u8981\u6d4f\u89c8\u5668\u505c\u6b62\u91cd\u65b0\u8fde\u63a5\uff0c\u90a3\u4e48\u5b83\u5e94\u8be5\u4f7f\u7528 HTTP \u72b6\u6001\u7801 204 \u8fdb\u884c\u54cd\u5e94\u3002<\/li>\n<li>\u5982\u679c\u6d4f\u89c8\u5668\u60f3\u8981\u5173\u95ed\u8fde\u63a5\uff0c\u5219\u5e94\u8be5\u8c03\u7528\u00a0<code>eventSource.close()<\/code>\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">let eventSource = new EventSource(...);\n\neventSource.close();\n<\/code><\/pre>\n<p>\u5e76\u4e14\uff0c\u5982\u679c\u54cd\u5e94\u5177\u6709\u4e0d\u6b63\u786e\u7684\u00a0<code>Content-Type<\/code>\u00a0\u6216\u8005\u5176 HTTP \u72b6\u6001\u7801\u4e0d\u662f 301\uff0c307\uff0c200 \u548c 204\uff0c\u5219\u4e0d\u4f1a\u8fdb\u884c\u91cd\u65b0\u8fde\u63a5\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u5c06\u4f1a\u53d1\u51fa\u00a0<code>&quot;error&quot;<\/code>\u00a0\u4e8b\u4ef6\uff0c\u5e76\u4e14\u6d4f\u89c8\u5668\u4e0d\u4f1a\u91cd\u65b0\u8fde\u63a5\u3002<\/p>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u5f53\u8fde\u63a5\u6700\u7ec8\u88ab\u5173\u95ed\u65f6\uff0c\u5c31\u65e0\u6cd5\u201c\u91cd\u65b0\u6253\u5f00\u201d\u5b83\u3002\u5982\u679c\u6211\u4eec\u60f3\u8981\u518d\u6b21\u8fde\u63a5\uff0c\u53ea\u9700\u8981\u521b\u5efa\u4e00\u4e2a\u65b0\u7684\u00a0<code>EventSource<\/code>\u3002<\/p>\n<\/blockquote>\n<h2>\u6d88\u606f id<\/h2>\n<p>\u5f53\u4e00\u4e2a\u8fde\u63a5\u7531\u4e8e\u7f51\u7edc\u95ee\u9898\u800c\u4e2d\u65ad\u65f6\uff0c\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u5668\u90fd\u65e0\u6cd5\u786e\u5b9a\u54ea\u4e9b\u6d88\u606f\u5df2\u7ecf\u6536\u5230\u54ea\u4e9b\u6ca1\u6709\u6536\u5230\u3002<br \/>\n\u4e3a\u4e86\u6b63\u786e\u5730\u6062\u590d\u8fde\u63a5\uff0c\u6bcf\u6761\u6d88\u606f\u90fd\u5e94\u8be5\u6709\u4e00\u4e2a\u00a0<code>id<\/code>\u00a0\u5b57\u6bb5\uff0c\u5c31\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-Text\">data: Message 1\nid: 1\n\ndata: Message 2\nid: 2\n\ndata: Message 3\ndata: of two lines\nid: 3\n<\/code><\/pre>\n<p>\u5f53\u6536\u5230\u5177\u6709\u00a0<code>id<\/code>\u00a0\u7684\u6d88\u606f\u65f6\uff0c\u6d4f\u89c8\u5668\u4f1a\uff1a<\/p>\n<ul>\n<li>\u5c06\u5c5e\u6027\u00a0<code>eventSource.lastEventId<\/code>\u00a0\u8bbe\u7f6e\u4e3a\u5176\u503c\u3002<\/li>\n<li>\u91cd\u65b0\u8fde\u63a5\u540e\uff0c\u53d1\u9001\u5e26\u6709\u00a0<code>id<\/code>\u00a0\u7684 header\u00a0<code>Last-Event-ID<\/code>\uff0c\u4ee5\u4fbf\u670d\u52a1\u5668\u53ef\u4ee5\u91cd\u65b0\u53d1\u9001\u540e\u9762\u7684\u6d88\u606f\u3002<\/li>\n<\/ul>\n<blockquote>\n<p>\u628a\u00a0<code>id:<\/code>\u00a0\u653e\u5728\u00a0<code>data:<\/code>\u00a0\u540e<br \/>\n\u8bf7\u6ce8\u610f\uff1a<code>id<\/code>\u00a0\u88ab\u670d\u52a1\u5668\u9644\u52a0\u5230\u00a0<code>data<\/code>\u00a0\u6d88\u606f\u540e\uff0c\u4ee5\u786e\u4fdd\u5728\u6536\u5230\u6d88\u606f\u540e\u00a0<code>lastEventId<\/code>\u00a0\u4f1a\u88ab\u66f4\u65b0\u3002<\/p>\n<\/blockquote>\n<h2>\u8fde\u63a5\u72b6\u6001 readyState<\/h2>\n<p><code>EventSource<\/code>\u00a0\u5bf9\u8c61\u6709\u00a0<code>readyState<\/code>\u00a0\u5c5e\u6027\uff0c\u8be5\u5c5e\u6027\u5177\u6709\u4e0b\u5217\u503c\u4e4b\u4e00\uff1a<\/p>\n<pre><code class=\"language-js\">EventSource.CONNECTING = 0; \/\/ \u8fde\u63a5\u4e2d\u6216\u8005\u91cd\u8fde\u4e2d\nEventSource.OPEN = 1;       \/\/ \u5df2\u8fde\u63a5\nEventSource.CLOSED = 2;     \/\/ \u8fde\u63a5\u5df2\u5173\u95ed\n<\/code><\/pre>\n<p>\u5bf9\u8c61\u521b\u5efa\u5b8c\u6210\u6216\u8005\u8fde\u63a5\u65ad\u5f00\u540e\uff0c\u5b83\u59cb\u7ec8\u662f\u00a0<code>EventSource.CONNECTING<\/code>\uff08\u7b49\u4e8e\u00a0<code>0<\/code>\uff09\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u67e5\u8be2\u8be5\u5c5e\u6027\u4ee5\u4e86\u89e3\u00a0<code>EventSource<\/code>\u00a0\u7684\u72b6\u6001\u3002<\/p>\n<h2>Event \u7c7b\u578b<\/h2>\n<p>\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u00a0<code>EventSource<\/code>\u00a0\u5bf9\u8c61\u751f\u6210\u4e09\u4e2a\u4e8b\u4ef6\uff1a<\/p>\n<ul>\n<li><code>message<\/code>\u00a0\u2014\u2014 \u6536\u5230\u6d88\u606f\uff0c\u53ef\u4ee5\u7528\u00a0<code>event.data<\/code>\u00a0\u8bbf\u95ee\u3002<\/li>\n<li><code>open<\/code>\u00a0\u2014\u2014 \u8fde\u63a5\u5df2\u6253\u5f00\u3002<\/li>\n<li><code>error<\/code>\u00a0\u2014\u2014 \u65e0\u6cd5\u5efa\u7acb\u8fde\u63a5\uff0c\u4f8b\u5982\uff0c\u670d\u52a1\u5668\u8fd4\u56de HTTP 500 \u72b6\u6001\u7801\u3002<br \/>\n\u670d\u52a1\u5668\u53ef\u4ee5\u5728\u4e8b\u4ef6\u5f00\u59cb\u65f6\u4f7f\u7528\u00a0<code>event: ...<\/code>\u00a0\u6307\u5b9a\u53e6\u4e00\u79cd\u7c7b\u578b\u4e8b\u4ef6\u3002<br \/>\n\u4f8b\u5982\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-Text\">event: join\ndata: Bob\n\ndata: Hello\n\nevent: leave\ndata: Bob\n<\/code><\/pre>\n<p>\u8981\u5904\u7406\u81ea\u5b9a\u4e49\u4e8b\u4ef6\uff0c\u6211\u4eec\u5fc5\u987b\u4f7f\u7528\u00a0<code>addEventListener<\/code>\u00a0\u800c\u975e\u00a0<code>onmessage<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">eventSource.addEventListener('join', event =&gt; {\n  alert(`Joined ${event.data}`);\n});\n\neventSource.addEventListener('message', event =&gt; {\n  alert(`Said: ${event.data}`);\n});\n\neventSource.addEventListener('leave', event =&gt; {\n  alert(`Left ${event.data}`);\n});\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Fetch JavaScript \u53ef\u4ee5\u5c06\u7f51\u7edc\u8bf7\u6c42\u53d1\u9001\u5230\u670d\u52a1\u5668\uff0c\u5e76\u5728\u9700\u8981\u65f6\u52a0\u8f7d\u65b0\u4fe1\u606f\u3002 \u4f8b\u5982\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u7f51\u7edc\u8bf7 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19],"tags":[],"class_list":["post-712","post","type-post","status-publish","format-standard","hentry","category-front-end"],"_links":{"self":[{"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts\/712","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=712"}],"version-history":[{"count":5,"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts\/712\/revisions"}],"predecessor-version":[{"id":737,"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts\/712\/revisions\/737"}],"wp:attachment":[{"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=712"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=712"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=712"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}