{"id":675,"date":"2024-06-22T16:11:45","date_gmt":"2024-06-22T08:11:45","guid":{"rendered":"https:\/\/levin.ink\/?p=675"},"modified":"2024-06-22T16:11:45","modified_gmt":"2024-06-22T08:11:45","slug":"js-3-12-%e6%a8%a1%e5%9d%97","status":"publish","type":"post","link":"https:\/\/levin.ink\/?p=675","title":{"rendered":"JS &#8211; 3-12 \u6a21\u5757"},"content":{"rendered":"<h1>\u6a21\u5757 Module \u7b80\u4ecb<\/h1>\n<p>\u968f\u7740\u6211\u4eec\u7684\u5e94\u7528\u8d8a\u6765\u8d8a\u5927\uff0c\u6211\u4eec\u60f3\u8981\u5c06\u5176\u62c6\u5206\u6210\u591a\u4e2a\u6587\u4ef6\uff0c\u5373\u6240\u8c13\u7684\u201c\u6a21\u5757\uff08module\uff09\u201d\u3002\u4e00\u4e2a\u6a21\u5757\u53ef\u4ee5\u5305\u542b\u7528\u4e8e\u7279\u5b9a\u76ee\u7684\u7684\u7c7b\u6216\u51fd\u6570\u5e93\u3002<br \/>\n\u5f88\u957f\u4e00\u6bb5\u65f6\u95f4\uff0cJavaScript \u90fd\u6ca1\u6709\u8bed\u8a00\u7ea7\uff08language-level\uff09\u7684\u6a21\u5757\u8bed\u6cd5\u3002\u8fd9\u4e0d\u662f\u4e00\u4e2a\u95ee\u9898\uff0c\u56e0\u4e3a\u6700\u521d\u7684\u811a\u672c\u53c8\u5c0f\u53c8\u7b80\u5355\uff0c\u6240\u4ee5\u6ca1\u5fc5\u8981\u5c06\u5176\u6a21\u5757\u5316\u3002<br \/>\n\u4f46\u662f\u6700\u7ec8\u811a\u672c\u53d8\u5f97\u8d8a\u6765\u8d8a\u590d\u6742\uff0c\u56e0\u6b64\u793e\u533a\u53d1\u660e\u4e86\u8bb8\u591a\u79cd\u65b9\u6cd5\u6765\u5c06\u4ee3\u7801\u7ec4\u7ec7\u5230\u6a21\u5757\u4e2d\uff0c\u4f7f\u7528\u7279\u6b8a\u7684\u5e93\u6309\u9700\u52a0\u8f7d\u6a21\u5757\u3002<br \/>\n\u5217\u4e3e\u4e00\u4e9b\uff08\u51fa\u4e8e\u5386\u53f2\u539f\u56e0\uff09\uff1a<\/p>\n<ul>\n<li><a href=\"https:\/\/en.wikipedia.org\/wiki\/Asynchronous_module_definition\">AMD<\/a>\u00a0\u2014\u2014 \u6700\u53e4\u8001\u7684\u6a21\u5757\u7cfb\u7edf\u4e4b\u4e00\uff0c\u6700\u521d\u7531\u00a0<a href=\"http:\/\/requirejs.org\/\">require.js<\/a>\u00a0\u5e93\u5b9e\u73b0\u3002<\/li>\n<li><a href=\"http:\/\/wiki.commonjs.org\/wiki\/Modules\/1.1\">CommonJS<\/a>\u00a0\u2014\u2014 \u4e3a Node.js \u670d\u52a1\u5668\u521b\u5efa\u7684\u6a21\u5757\u7cfb\u7edf\u3002<\/li>\n<li><a href=\"https:\/\/github.com\/umdjs\/umd\">UMD<\/a>\u00a0\u2014\u2014 \u53e6\u5916\u4e00\u4e2a\u6a21\u5757\u7cfb\u7edf\uff0c\u5efa\u8bae\u4f5c\u4e3a\u901a\u7528\u7684\u6a21\u5757\u7cfb\u7edf\uff0c\u5b83\u4e0e AMD \u548c CommonJS \u90fd\u517c\u5bb9\u3002<br \/>\n\u73b0\u5728\uff0c\u5b83\u4eec\u90fd\u5728\u6162\u6162\u6210\u4e3a\u5386\u53f2\u7684\u4e00\u90e8\u5206\uff0c\u4f46\u6211\u4eec\u4ecd\u7136\u53ef\u4ee5\u5728\u65e7\u811a\u672c\u4e2d\u627e\u5230\u5b83\u4eec\u3002<br \/>\n\u8bed\u8a00\u7ea7\u7684\u6a21\u5757\u7cfb\u7edf\u5728 2015 \u5e74\u7684\u65f6\u5019\u51fa\u73b0\u5728\u4e86\u6807\u51c6\uff08ES6\uff09\u4e2d\uff0c\u6b64\u540e\u9010\u6e10\u53d1\u5c55\uff0c\u73b0\u5728\u5df2\u7ecf\u5f97\u5230\u4e86\u6240\u6709\u4e3b\u6d41\u6d4f\u89c8\u5668\u548c Node.js \u7684\u652f\u6301\u3002\u56e0\u6b64\uff0c\u6211\u4eec\u5c06\u4ece\u73b0\u5728\u5f00\u59cb\u5b66\u4e60\u73b0\u4ee3 JavaScript \u6a21\u5757\uff08module\uff09\u3002<\/li>\n<\/ul>\n<h2>\u4ec0\u4e48\u662f\u6a21\u5757\uff1f<\/h2>\n<p>\u4e00\u4e2a\u6a21\u5757\uff08module\uff09\u5c31\u662f\u4e00\u4e2a\u6587\u4ef6\u3002\u4e00\u4e2a\u811a\u672c\u5c31\u662f\u4e00\u4e2a\u6a21\u5757\u3002\u5c31\u8fd9\u4e48\u7b80\u5355\u3002<br \/>\n\u6a21\u5757\u53ef\u4ee5\u76f8\u4e92\u52a0\u8f7d\uff0c\u5e76\u53ef\u4ee5\u4f7f\u7528\u7279\u6b8a\u7684\u6307\u4ee4\u00a0<code>export<\/code>\u00a0\u548c\u00a0<code>import<\/code>\u00a0\u6765\u4ea4\u6362\u529f\u80fd\uff0c\u4ece\u53e6\u4e00\u4e2a\u6a21\u5757\u8c03\u7528\u4e00\u4e2a\u6a21\u5757\u7684\u51fd\u6570\uff1a<\/p>\n<ul>\n<li><code>export<\/code>\u00a0\u5173\u952e\u5b57\u6807\u8bb0\u4e86\u53ef\u4ee5\u4ece\u5f53\u524d\u6a21\u5757\u5916\u90e8\u8bbf\u95ee\u7684\u53d8\u91cf\u548c\u51fd\u6570\u3002<\/li>\n<li><code>import<\/code>\u00a0\u5173\u952e\u5b57\u5141\u8bb8\u4ece\u5176\u4ed6\u6a21\u5757\u5bfc\u5165\u529f\u80fd\u3002<br \/>\n\u4f8b\u5982\uff0c\u6211\u4eec\u6709\u4e00\u4e2a\u00a0<code>sayHi.js<\/code>\u00a0\u6587\u4ef6\u5bfc\u51fa\u4e86\u4e00\u4e2a\u51fd\u6570\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 sayHi.js\nexport function sayHi(user) {\n  alert(`Hello, ${user}!`);\n}\n<\/code><\/pre>\n<p>\u2026\u2026\u7136\u540e\u53e6\u4e00\u4e2a\u6587\u4ef6\u53ef\u80fd\u5bfc\u5165\u5e76\u4f7f\u7528\u4e86\u8fd9\u4e2a\u51fd\u6570\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport { sayHi } from '.\/sayHi.js';\n\nalert(sayHi); \/\/ function...\nsayHi('John'); \/\/ Hello, John!\n<\/code><\/pre>\n<p><code>import<\/code>\u00a0\u6307\u4ee4\u901a\u8fc7\u76f8\u5bf9\u4e8e\u5f53\u524d\u6587\u4ef6\u7684\u8def\u5f84\u00a0<code>.\/sayHi.js<\/code>\u00a0\u52a0\u8f7d\u6a21\u5757\uff0c\u5e76\u5c06\u5bfc\u5165\u7684\u51fd\u6570\u00a0<code>sayHi<\/code>\u00a0\u5206\u914d\uff08assign\uff09\u7ed9\u76f8\u5e94\u7684\u53d8\u91cf\u3002<br \/>\n\u8ba9\u6211\u4eec\u5728\u6d4f\u89c8\u5668\u4e2d\u8fd0\u884c\u4e00\u4e0b\u8fd9\u4e2a\u793a\u4f8b\u3002<br \/>\n\u7531\u4e8e\u6a21\u5757\u652f\u6301\u7279\u6b8a\u7684\u5173\u952e\u5b57\u548c\u529f\u80fd\uff0c\u56e0\u6b64\u6211\u4eec\u5fc5\u987b\u901a\u8fc7\u4f7f\u7528\u00a0<code>&lt;script type=&quot;module&quot;&gt;<\/code>\u00a0\u7279\u6027\uff08attribute\uff09\u6765\u544a\u8bc9\u6d4f\u89c8\u5668\uff0c\u6b64\u811a\u672c\u5e94\u8be5\u88ab\u5f53\u4f5c\u6a21\u5757\uff08module\uff09\u6765\u5bf9\u5f85\u3002<\/p>\n<pre><code class=\"language-html\">&lt;!doctype html&gt;\n&lt;script type=&quot;module&quot;&gt;\n  import {sayHi} from '.\/say.js';\n\n  document.body.innerHTML = sayHi('John');\n&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u6d4f\u89c8\u5668\u4f1a\u81ea\u52a8\u83b7\u53d6\u5e76\u89e3\u6790\uff08evaluate\uff09\u5bfc\u5165\u7684\u6a21\u5757\uff08\u5982\u679c\u9700\u8981\uff0c\u8fd8\u53ef\u4ee5\u5206\u6790\u8be5\u6a21\u5757\u7684\u5bfc\u5165\uff09\uff0c\u7136\u540e\u8fd0\u884c\u8be5\u811a\u672c\u3002<\/p>\n<blockquote>\n<p>\u6a21\u5757\u53ea\u901a\u8fc7 HTTP(s) \u5de5\u4f5c\uff0c\u800c\u975e\u672c\u5730<br \/>\n\u5982\u679c\u4f60\u5c1d\u8bd5\u901a\u8fc7\u00a0<code>file:\/\/<\/code>\u00a0\u534f\u8bae\u5728\u672c\u5730\u6253\u5f00\u4e00\u4e2a\u7f51\u9875\uff0c\u4f60\u4f1a\u53d1\u73b0\u00a0<code>import\/export<\/code>\u00a0\u6307\u4ee4\u4e0d\u8d77\u4f5c\u7528\u3002\u4f60\u53ef\u4ee5\u4f7f\u7528\u672c\u5730 Web \u670d\u52a1\u5668\uff0c\u4f8b\u5982\u00a0<a href=\"https:\/\/www.npmjs.com\/package\/static-server#getting-started\">static-server<\/a>\uff0c\u6216\u8005\u4f7f\u7528\u7f16\u8f91\u5668\u7684\u201c\u5b9e\u65f6\u670d\u52a1\u5668\u201d\u529f\u80fd\uff0c\u4f8b\u5982 VS Code \u7684\u00a0<a href=\"https:\/\/marketplace.visualstudio.com\/items?itemName=ritwickdey.LiveServer\">Live Server Extension<\/a>\u00a0\u6765\u6d4b\u8bd5\u6a21\u5757\u3002<\/p>\n<\/blockquote>\n<h2>\u6a21\u5757\u6838\u5fc3\u529f\u80fd<\/h2>\n<p>\u4e0e\u201c\u5e38\u89c4\u201d\u811a\u672c\u76f8\u6bd4\uff0c\u6a21\u5757\u6709\u4ec0\u4e48\u4e0d\u540c\u5462\uff1f<br \/>\n\u4e0b\u9762\u662f\u4e00\u4e9b\u6838\u5fc3\u7684\u529f\u80fd\uff0c\u5bf9\u6d4f\u89c8\u5668\u548c\u670d\u52a1\u7aef\u7684 JavaScript \u6765\u8bf4\u90fd\u6709\u6548\u3002<\/p>\n<h3>\u59cb\u7ec8\u4f7f\u7528 &quot;use strict&quot;<\/h3>\n<p>\u6a21\u5757\u59cb\u7ec8\u5728\u4e25\u683c\u6a21\u5f0f\u4e0b\u8fd0\u884c\u3002\u4f8b\u5982\uff0c\u5bf9\u4e00\u4e2a\u672a\u58f0\u660e\u7684\u53d8\u91cf\u8d4b\u503c\u5c06\u4ea7\u751f\u9519\u8bef\uff08\u8bd1\u6ce8\uff1a\u5728\u6d4f\u89c8\u5668\u63a7\u5236\u53f0\u53ef\u4ee5\u770b\u5230 error \u4fe1\u606f\uff09\u3002<\/p>\n<pre><code class=\"language-js\">&lt;script type=&quot;module&quot;&gt;\n  a = 5; \/\/ error\n&lt;\/script&gt;\n<\/code><\/pre>\n<h3>\u6a21\u5757\u7ea7\u4f5c\u7528\u57df<\/h3>\n<p>\u6bcf\u4e2a\u6a21\u5757\u90fd\u6709\u81ea\u5df1\u7684\u9876\u7ea7\u4f5c\u7528\u57df\uff08top-level scope\uff09\u3002\u6362\u53e5\u8bdd\u8bf4\uff0c\u4e00\u4e2a\u6a21\u5757\u4e2d\u7684\u9876\u7ea7\u4f5c\u7528\u57df\u53d8\u91cf\u548c\u51fd\u6570\u5728\u5176\u4ed6\u811a\u672c\u4e2d\u662f\u4e0d\u53ef\u89c1\u7684\u3002<br \/>\n\u5728\u4e0b\u9762\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u5bfc\u5165\u4e86\u4e24\u4e2a\u811a\u672c\uff0c<code>hello.js<\/code>\u00a0\u5c1d\u8bd5\u4f7f\u7528\u5728\u00a0<code>user.js<\/code>\u00a0\u4e2d\u58f0\u660e\u7684\u53d8\u91cf\u00a0<code>user<\/code>\u3002\u5b83\u5931\u8d25\u4e86\uff0c\u56e0\u4e3a\u5b83\u662f\u4e00\u4e2a\u5355\u72ec\u7684\u6a21\u5757\uff08\u4f60\u5728\u63a7\u5236\u53f0\u4e2d\u53ef\u4ee5\u770b\u5230\u62a5\u9519\uff09\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 hello.js\nalert(user); \/\/ no such variable (each module has independent variables)\n\n\/\/ \ud83d\udcc1 user.js\nlet user = &quot;John&quot;;\n<\/code><\/pre>\n<pre><code class=\"language-html\">\/\/ \ud83d\udcc1 index.html\n&lt;!doctype html&gt;\n&lt;script type=&quot;module&quot; src=&quot;user.js&quot;&gt;&lt;\/script&gt;\n&lt;script type=&quot;module&quot; src=&quot;hello.js&quot;&gt;&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u6a21\u5757\u5e94\u8be5\u00a0<code>export<\/code>\u00a0\u5b83\u4eec\u60f3\u8981\u88ab\u5916\u90e8\u8bbf\u95ee\u7684\u5185\u5bb9\uff0c\u5e76\u00a0<code>import<\/code>\u00a0\u5b83\u4eec\u6240\u9700\u8981\u7684\u5185\u5bb9\u3002<\/p>\n<ul>\n<li><code>user.js<\/code>\u00a0\u5e94\u8be5\u5bfc\u51fa\u00a0<code>user<\/code>\u00a0\u53d8\u91cf\u3002<\/li>\n<li><code>hello.js<\/code>\u00a0\u5e94\u8be5\u4ece\u00a0<code>user.js<\/code>\u00a0\u6a21\u5757\u4e2d\u5bfc\u5165\u5b83\u3002<br \/>\n\u6362\u53e5\u8bdd\u8bf4\uff0c\u5bf9\u4e8e\u6a21\u5757\uff0c\u6211\u4eec\u4f7f\u7528\u5bfc\u5165\/\u5bfc\u51fa\u800c\u4e0d\u662f\u4f9d\u8d56\u5168\u5c40\u53d8\u91cf\u3002<br \/>\n\u8fd9\u662f\u6b63\u786e\u7684\u53d8\u4f53\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 hello.js\nimport {user} from '.\/user.js';\n\ndocument.body.innerHTML = user; \/\/ John\n\n\/\/ \ud83d\udcc1 user.js\nexport let user = &quot;John&quot;;\n<\/code><\/pre>\n<pre><code class=\"language-html\">\/\/ \ud83d\udcc1 index.html\n&lt;!doctype html&gt;\n&lt;script type=&quot;module&quot; src=&quot;hello.js&quot;&gt;&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u5728\u6d4f\u89c8\u5668\u4e2d\uff0c\u5bf9\u4e8e HTML \u9875\u9762\uff0c\u6bcf\u4e2a\u00a0<code>&lt;script type=&quot;module&quot;&gt;<\/code>\u00a0\u90fd\u5b58\u5728\u72ec\u7acb\u7684\u9876\u7ea7\u4f5c\u7528\u57df\u3002<br \/>\n\u4e0b\u9762\u662f\u540c\u4e00\u9875\u9762\u4e0a\u7684\u4e24\u4e2a\u811a\u672c\uff0c\u90fd\u662f\u00a0<code>type=&quot;module&quot;<\/code>\u3002\u5b83\u4eec\u770b\u4e0d\u5230\u5f7c\u6b64\u7684\u9876\u7ea7\u53d8\u91cf\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;script type=&quot;module&quot;&gt;\n  \/\/ \u53d8\u91cf\u4ec5\u5728\u8fd9\u4e2a module script \u5185\u53ef\u89c1\n  let user = &quot;John&quot;;\n&lt;\/script&gt;\n\n&lt;script type=&quot;module&quot;&gt;\n  alert(user); \/\/ Error: user is not defined\n&lt;\/script&gt;\n<\/code><\/pre>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u5728\u6d4f\u89c8\u5668\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5c06\u53d8\u91cf\u663e\u5f0f\u5730\u5206\u914d\u7ed9\u00a0<code>window<\/code>\u00a0\u7684\u4e00\u4e2a\u5c5e\u6027\uff0c\u4f7f\u5176\u6210\u4e3a\u7a97\u53e3\u7ea7\u522b\u7684\u5168\u5c40\u53d8\u91cf\u3002\u4f8b\u5982\u00a0<code>window.user = &quot;John&quot;<\/code>\u3002<br \/>\n\u8fd9\u6837\u6240\u6709\u811a\u672c\u90fd\u4f1a\u770b\u5230\u5b83\uff0c\u65e0\u8bba\u811a\u672c\u662f\u5426\u5e26\u6709\u00a0<code>type=&quot;module&quot;<\/code>\u3002<br \/>\n\u4e5f\u5c31\u662f\u8bf4\uff0c\u521b\u5efa\u8fd9\u79cd\u5168\u5c40\u53d8\u91cf\u5e76\u4e0d\u662f\u4e00\u4e2a\u597d\u7684\u65b9\u5f0f\u3002\u8bf7\u5c3d\u91cf\u907f\u514d\u8fd9\u6837\u505a\u3002<\/p>\n<\/blockquote>\n<h3>\u6a21\u5757\u4ee3\u7801\u4ec5\u5728\u7b2c\u4e00\u6b21\u5bfc\u5165\u65f6\u88ab\u89e3\u6790<\/h3>\n<p>\u5982\u679c\u540c\u4e00\u4e2a\u6a21\u5757\u88ab\u5bfc\u5165\u5230\u591a\u4e2a\u5176\u4ed6\u4f4d\u7f6e\uff0c\u90a3\u4e48\u5b83\u7684\u4ee3\u7801\u53ea\u4f1a\u6267\u884c\u4e00\u6b21\uff0c\u5373\u5728\u7b2c\u4e00\u6b21\u88ab\u5bfc\u5165\u65f6\u3002\u7136\u540e\u5c06\u5176\u5bfc\u51fa\uff08export\uff09\u7684\u5185\u5bb9\u63d0\u4f9b\u7ed9\u8fdb\u4e00\u6b65\u7684\u5bfc\u5165\uff08importer\uff09\u3002<br \/>\n\u53ea\u6267\u884c\u4e00\u6b21\u4f1a\u4ea7\u751f\u5f88\u91cd\u8981\u7684\u5f71\u54cd\uff0c\u6211\u4eec\u5e94\u8be5\u610f\u8bc6\u5230\u8fd9\u4e00\u70b9\u3002<br \/>\n\u8ba9\u6211\u4eec\u770b\u51e0\u4e2a\u4f8b\u5b50\u3002<br \/>\n\u9996\u5148\uff0c\u5982\u679c\u6267\u884c\u4e00\u4e2a\u6a21\u5757\u4e2d\u7684\u4ee3\u7801\u4f1a\u5e26\u6765\u526f\u4f5c\u7528\uff08side-effect\uff09\uff0c\u4f8b\u5982\u663e\u793a\u4e00\u6761\u6d88\u606f\uff0c\u90a3\u4e48\u591a\u6b21\u5bfc\u5165\u5b83\u53ea\u4f1a\u89e6\u53d1\u4e00\u6b21\u663e\u793a \u2014\u2014 \u5373\u7b2c\u4e00\u6b21\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 alert.js\nalert(&quot;Module is evaluated!&quot;);\n<\/code><\/pre>\n<pre><code class=\"language-js\">\/\/ \u5728\u4e0d\u540c\u7684\u6587\u4ef6\u4e2d\u5bfc\u5165\u76f8\u540c\u7684\u6a21\u5757\n\n\/\/ \ud83d\udcc1 1.js\nimport `.\/alert.js`; \/\/ Module is evaluated!\n\n\/\/ \ud83d\udcc1 2.js\nimport `.\/alert.js`; \/\/ (\u4ec0\u4e48\u90fd\u4e0d\u663e\u793a)\n<\/code><\/pre>\n<p>\u7b2c\u4e8c\u6b21\u5bfc\u5165\u4ec0\u4e48\u4e5f\u6ca1\u663e\u793a\uff0c\u56e0\u4e3a\u6a21\u5757\u5df2\u7ecf\u6267\u884c\u8fc7\u4e86\u3002<br \/>\n\u8fd9\u91cc\u6709\u4e00\u6761\u89c4\u5219\uff1a\u9876\u5c42\u6a21\u5757\u4ee3\u7801\u5e94\u8be5\u7528\u4e8e\u521d\u59cb\u5316\uff0c\u521b\u5efa\u6a21\u5757\u7279\u5b9a\u7684\u5185\u90e8\u6570\u636e\u7ed3\u6784\u3002\u5982\u679c\u6211\u4eec\u9700\u8981\u591a\u6b21\u8c03\u7528\u67d0\u4e9b\u4e1c\u897f \u2014\u2014 \u6211\u4eec\u5e94\u8be5\u5c06\u5176\u4ee5\u51fd\u6570\u7684\u5f62\u5f0f\u5bfc\u51fa\uff0c\u5c31\u50cf\u6211\u4eec\u5728\u4e0a\u9762\u4f7f\u7528\u00a0<code>sayHi<\/code>\u00a0\u90a3\u6837\u3002<br \/>\n\u73b0\u5728\uff0c\u8ba9\u6211\u4eec\u770b\u4e00\u4e2a\u66f4\u590d\u6742\u7684\u4f8b\u5b50\u3002<br \/>\n\u6211\u4eec\u5047\u8bbe\u4e00\u4e2a\u6a21\u5757\u5bfc\u51fa\u4e86\u4e00\u4e2a\u5bf9\u8c61\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 admin.js\nexport let admin = {\n  name: &quot;John&quot;\n};\n<\/code><\/pre>\n<p>\u5982\u679c\u8fd9\u4e2a\u6a21\u5757\u88ab\u5bfc\u5165\u5230\u591a\u4e2a\u6587\u4ef6\u4e2d\uff0c\u6a21\u5757\u4ec5\u5728\u7b2c\u4e00\u6b21\u88ab\u5bfc\u5165\u65f6\u88ab\u89e3\u6790\uff0c\u5e76\u521b\u5efa\u00a0<code>admin<\/code>\u00a0\u5bf9\u8c61\uff0c\u7136\u540e\u5c06\u5176\u4f20\u5165\u5230\u6240\u6709\u7684\u5bfc\u5165\u3002<br \/>\n\u6240\u6709\u7684\u5bfc\u5165\u90fd\u53ea\u83b7\u5f97\u4e86\u4e00\u4e2a\u552f\u4e00\u7684\u00a0<code>admin<\/code>\u00a0\u5bf9\u8c61\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 1.js\nimport { admin } from '.\/admin.js';\nadmin.name = &quot;Pete&quot;;\n\n\/\/ \ud83d\udcc1 2.js\nimport { admin } from '.\/admin.js';\nalert(admin.name); \/\/ Pete\n\n\/\/ 1.js \u548c 2.js \u5f15\u7528\u7684\u662f\u540c\u4e00\u4e2a admin \u5bf9\u8c61\n\/\/ \u5728 1.js \u4e2d\u5bf9\u5bf9\u8c61\u505a\u7684\u66f4\u6539\uff0c\u5728 2.js \u4e2d\u4e5f\u662f\u53ef\u89c1\u7684\n<\/code><\/pre>\n<p>\u6b63\u5982\u4f60\u6240\u770b\u5230\u7684\uff0c\u5f53\u5728\u00a0<code>1.js<\/code>\u00a0\u4e2d\u4fee\u6539\u4e86\u5bfc\u5165\u7684\u00a0<code>admin<\/code>\u00a0\u4e2d\u7684\u00a0<code>name<\/code>\u00a0\u5c5e\u6027\u65f6\uff0c\u6211\u4eec\u5728\u00a0<code>2.js<\/code>\u00a0\u4e2d\u53ef\u4ee5\u770b\u5230\u65b0\u7684\u00a0<code>admin.name<\/code>\u3002<br \/>\n\u8fd9\u6b63\u662f\u56e0\u4e3a\u8be5\u6a21\u5757\u53ea\u6267\u884c\u4e86\u4e00\u6b21\u3002\u751f\u6210\u5bfc\u51fa\uff0c\u7136\u540e\u8fd9\u4e9b\u5bfc\u51fa\u5728\u5bfc\u5165\u4e4b\u95f4\u5171\u4eab\uff0c\u56e0\u6b64\u5982\u679c\u66f4\u6539\u4e86\u00a0<code>admin<\/code>\u00a0\u5bf9\u8c61\uff0c\u5728\u5176\u4ed6\u5bfc\u5165\u4e2d\u4e5f\u4f1a\u770b\u5230\u3002<br \/>\n<strong>\u8fd9\u79cd\u884c\u4e3a\u5b9e\u9645\u4e0a\u975e\u5e38\u65b9\u4fbf\uff0c\u56e0\u4e3a\u5b83\u5141\u8bb8\u6211\u4eec\u201c\u914d\u7f6e\u201d\u6a21\u5757\u3002<\/strong><br \/>\n\u6362\u53e5\u8bdd\u8bf4\uff0c\u6a21\u5757\u53ef\u4ee5\u63d0\u4f9b\u9700\u8981\u914d\u7f6e\u7684\u901a\u7528\u529f\u80fd\u3002\u4f8b\u5982\u8eab\u4efd\u9a8c\u8bc1\u9700\u8981\u51ed\u8bc1\u3002\u90a3\u4e48\u6a21\u5757\u53ef\u4ee5\u5bfc\u51fa\u4e00\u4e2a\u914d\u7f6e\u5bf9\u8c61\uff0c\u671f\u671b\u5916\u90e8\u4ee3\u7801\u53ef\u4ee5\u5bf9\u5176\u8fdb\u884c\u8d4b\u503c\u3002<br \/>\n\u8fd9\u662f\u7ecf\u5178\u7684\u4f7f\u7528\u6a21\u5f0f\uff1a<\/p>\n<ol>\n<li>\u6a21\u5757\u5bfc\u51fa\u4e00\u4e9b\u914d\u7f6e\u65b9\u6cd5\uff0c\u4f8b\u5982\u4e00\u4e2a\u914d\u7f6e\u5bf9\u8c61\u3002<\/li>\n<li>\u5728\u7b2c\u4e00\u6b21\u5bfc\u5165\u65f6\uff0c\u6211\u4eec\u5bf9\u5176\u8fdb\u884c\u521d\u59cb\u5316\uff0c\u5199\u5165\u5176\u5c5e\u6027\u3002\u53ef\u4ee5\u5728\u5e94\u7528\u9876\u7ea7\u811a\u672c\u4e2d\u8fdb\u884c\u6b64\u64cd\u4f5c\u3002<\/li>\n<li>\u8fdb\u4e00\u6b65\u5730\u5bfc\u5165\u4f7f\u7528\u6a21\u5757\u3002<br \/>\n\u4f8b\u5982\uff0c<code>admin.js<\/code>\u00a0\u6a21\u5757\u53ef\u80fd\u63d0\u4f9b\u4e86\u67d0\u4e9b\u529f\u80fd\uff08\u4f8b\u5982\u8eab\u4efd\u9a8c\u8bc1\uff09\uff0c\u4f46\u5e0c\u671b\u51ed\u8bc1\u53ef\u4ee5\u4ece\u6a21\u5757\u4e4b\u5916\u8d4b\u503c\u5230\u00a0<code>config<\/code>\u00a0\u5bf9\u8c61\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 admin.js\nexport let config = { };\n\nexport function sayHi() {\n  alert(`Ready to serve, ${config.user}!`);\n}\n<\/code><\/pre>\n<p>\u8fd9\u91cc\uff0c<code>admin.js<\/code>\u00a0\u5bfc\u51fa\u4e86\u00a0<code>config<\/code>\u00a0\u5bf9\u8c61\uff08\u6700\u521d\u662f\u7a7a\u7684\uff0c\u4f46\u4e5f\u53ef\u80fd\u6709\u9ed8\u8ba4\u5c5e\u6027\uff09\u3002<br \/>\n\u7136\u540e\uff0c\u5728\u00a0<code>init.js<\/code>\u00a0\u4e2d\uff0c\u6211\u4eec\u5e94\u7528\u7684\u7b2c\u4e00\u4e2a\u811a\u672c\uff0c\u6211\u4eec\u4ece\u00a0<code>init.js<\/code>\u00a0\u5bfc\u5165\u4e86\u00a0<code>config<\/code>\u00a0\u5e76\u8bbe\u7f6e\u4e86\u00a0<code>config.user<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 init.js\nimport { config } from '.\/admin.js';\nconfig.user = &quot;Pete&quot;;\n<\/code><\/pre>\n<p>\u2026\u2026\u73b0\u5728\u6a21\u5757\u00a0<code>admin.js<\/code>\u00a0\u5df2\u7ecf\u662f\u88ab\u914d\u7f6e\u8fc7\u7684\u4e86\u3002<br \/>\n\u5176\u4ed6\u5bfc\u5165\u53ef\u4ee5\u8c03\u7528\u5b83\uff0c\u5b83\u4f1a\u6b63\u786e\u663e\u793a\u5f53\u524d\u7528\u6237\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 another.js\nimport { sayHi } from '.\/admin.js';\n\nsayHi(); \/\/ Ready to serve, Pete!\n<\/code><\/pre>\n<h3>import.meta<\/h3>\n<p><code>import.meta<\/code>\u00a0\u5bf9\u8c61\u5305\u542b\u5173\u4e8e\u5f53\u524d\u6a21\u5757\u7684\u4fe1\u606f\u3002<br \/>\n\u5b83\u7684\u5185\u5bb9\u53d6\u51b3\u4e8e\u5176\u6240\u5728\u7684\u73af\u5883\u3002\u5728\u6d4f\u89c8\u5668\u73af\u5883\u4e2d\uff0c\u5b83\u5305\u542b\u5f53\u524d\u811a\u672c\u7684 URL\uff0c\u6216\u8005\u5982\u679c\u5b83\u662f\u5728 HTML \u4e2d\u7684\u8bdd\uff0c\u5219\u5305\u542b\u5f53\u524d\u9875\u9762\u7684 URL\u3002<\/p>\n<pre><code class=\"language-html\">&lt;script type=&quot;module&quot;&gt;\n  alert(import.meta.url); \/\/ \u811a\u672c\u7684 URL\n  \/\/ \u5bf9\u4e8e\u5185\u8054\u811a\u672c\u6765\u8bf4\uff0c\u5219\u662f\u5f53\u524d HTML \u9875\u9762\u7684 URL\n&lt;\/script&gt;\n<\/code><\/pre>\n<h3>\u5728\u4e00\u4e2a\u6a21\u5757\u4e2d &quot;this&quot; \u662f undefined<\/h3>\n<p>\u8fd9\u662f\u4e00\u4e2a\u5c0f\u529f\u80fd\uff0c\u4f46\u4e3a\u4e86\u5b8c\u6574\u6027\uff0c\u6211\u4eec\u5e94\u8be5\u63d0\u5230\u5b83\u3002<br \/>\n\u5728\u4e00\u4e2a\u6a21\u5757\u4e2d\uff0c\u9876\u7ea7\u00a0<code>this<\/code>\u00a0\u662f undefined\u3002<br \/>\n\u5c06\u5176\u4e0e\u975e\u6a21\u5757\u811a\u672c\u8fdb\u884c\u6bd4\u8f83\u4f1a\u53d1\u73b0\uff0c\u975e\u6a21\u5757\u811a\u672c\u7684\u9876\u7ea7\u00a0<code>this<\/code>\u00a0\u662f\u5168\u5c40\u5bf9\u8c61\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;script&gt;\n  alert(this); \/\/ window\n&lt;\/script&gt;\n\n&lt;script type=&quot;module&quot;&gt;\n  alert(this); \/\/ undefined\n&lt;\/script&gt;\n<\/code><\/pre>\n<h2>\u6d4f\u89c8\u5668\u7279\u5b9a\u529f\u80fd<\/h2>\n<p>\u4e0e\u5e38\u89c4\u811a\u672c\u76f8\u6bd4\uff0c\u62e5\u6709\u00a0<code>type=&quot;module&quot;<\/code>\u00a0\u6807\u8bc6\u7684\u811a\u672c\u6709\u4e00\u4e9b\u7279\u5b9a\u4e8e\u6d4f\u89c8\u5668\u7684\u5dee\u5f02\u3002<br \/>\n\u5982\u679c\u4f60\u662f\u7b2c\u4e00\u6b21\u9605\u8bfb\u6216\u8005\u4f60\u4e0d\u6253\u7b97\u5728\u6d4f\u89c8\u5668\u4e2d\u4f7f\u7528 JavaScript\uff0c\u90a3\u4e48\u4f60\u53ef\u4ee5\u8df3\u8fc7\u672c\u8282\u5185\u5bb9\u3002<\/p>\n<h3>\u6a21\u5757\u811a\u672c\u662f\u5ef6\u8fdf\u7684<\/h3>\n<p>\u6a21\u5757\u811a\u672c\u00a0<strong>\u603b\u662f<\/strong>\u00a0\u88ab\u5ef6\u8fdf\u7684\uff0c\u4e0e\u00a0<code>defer<\/code>\u00a0\u7279\u6027\uff08\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/script-async-defer\">\u811a\u672c\uff1aasync\uff0cdefer<\/a>\u00a0\u4e00\u7ae0\u4e2d\u63cf\u8ff0\u7684\uff09\u5bf9\u5916\u90e8\u811a\u672c\u548c\u5185\u8054\u811a\u672c\uff08inline script\uff09\u7684\u5f71\u54cd\u76f8\u540c\u3002<br \/>\n\u4e5f\u5c31\u662f\u8bf4\uff1a<\/p>\n<ul>\n<li>\u4e0b\u8f7d\u5916\u90e8\u6a21\u5757\u811a\u672c\u00a0<code>&lt;script type=&quot;module&quot; src=&quot;...&quot;&gt;<\/code>\u00a0\u4e0d\u4f1a\u963b\u585e HTML \u7684\u5904\u7406\uff0c\u5b83\u4eec\u4f1a\u4e0e\u5176\u4ed6\u8d44\u6e90\u5e76\u884c\u52a0\u8f7d\u3002<\/li>\n<li>\u6a21\u5757\u811a\u672c\u4f1a\u7b49\u5230 HTML \u6587\u6863\u5b8c\u5168\u51c6\u5907\u5c31\u7eea\uff08\u5373\u4f7f\u5b83\u4eec\u5f88\u5c0f\u5e76\u4e14\u6bd4 HTML \u52a0\u8f7d\u901f\u5ea6\u66f4\u5feb\uff09\uff0c\u7136\u540e\u624d\u4f1a\u8fd0\u884c\u3002<\/li>\n<li>\u4fdd\u6301\u811a\u672c\u7684\u76f8\u5bf9\u987a\u5e8f\uff1a\u5728\u6587\u6863\u4e2d\u6392\u5728\u524d\u9762\u7684\u811a\u672c\u5148\u6267\u884c\u3002<br \/>\n\u5b83\u7684\u4e00\u4e2a\u526f\u4f5c\u7528\u662f\uff0c\u6a21\u5757\u811a\u672c\u603b\u662f\u4f1a\u201c\u770b\u5230\u201d\u5df2\u5b8c\u5168\u52a0\u8f7d\u7684 HTML \u9875\u9762\uff0c\u5305\u62ec\u5728\u5b83\u4eec\u4e0b\u65b9\u7684 HTML \u5143\u7d20\u3002<br \/>\n\u4f8b\u5982\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-html\">&lt;script type=&quot;module&quot;&gt;\n  alert(typeof button); \/\/ object\uff1a\u811a\u672c\u53ef\u4ee5\u201c\u770b\u89c1\u201d\u4e0b\u9762\u7684 button\n  \/\/ \u56e0\u4e3a\u6a21\u5757\u662f\u88ab\u5ef6\u8fdf\u7684\uff08deferred\uff0c\u6240\u4ee5\u6a21\u5757\u811a\u672c\u4f1a\u5728\u6574\u4e2a\u9875\u9762\u52a0\u8f7d\u5b8c\u6210\u540e\u624d\u8fd0\u884c\n&lt;\/script&gt;\n\n\u76f8\u8f83\u4e8e\u4e0b\u9762\u8fd9\u4e2a\u5e38\u89c4\u811a\u672c\uff1a\n\n&lt;script&gt;\n  alert(typeof button); \/\/ button \u4e3a undefined\uff0c\u811a\u672c\u770b\u4e0d\u5230\u4e0b\u9762\u7684\u5143\u7d20\n  \/\/ \u5e38\u89c4\u811a\u672c\u4f1a\u7acb\u5373\u8fd0\u884c\uff0c\u5e38\u89c4\u811a\u672c\u7684\u8fd0\u884c\u662f\u5728\u5728\u5904\u7406\u9875\u9762\u7684\u5176\u4f59\u90e8\u5206\u4e4b\u524d\u8fdb\u884c\u7684\n&lt;\/script&gt;\n\n&lt;button id=&quot;button&quot;&gt;Button&lt;\/button&gt;\n<\/code><\/pre>\n<p>\u8bf7\u6ce8\u610f\uff1a\u4e0a\u9762\u7684\u7b2c\u4e8c\u4e2a\u811a\u672c\u5b9e\u9645\u4e0a\u8981\u5148\u4e8e\u524d\u4e00\u4e2a\u811a\u672c\u8fd0\u884c\uff01\u6240\u4ee5\u6211\u4eec\u4f1a\u5148\u770b\u5230\u00a0<code>undefined<\/code>\uff0c\u7136\u540e\u624d\u662f\u00a0<code>object<\/code>\u3002<br \/>\n\u8fd9\u662f\u56e0\u4e3a\u6a21\u5757\u811a\u672c\u662f\u88ab\u5ef6\u8fdf\u7684\uff0c\u6240\u4ee5\u8981\u7b49\u5230 HTML \u6587\u6863\u88ab\u5904\u7406\u5b8c\u6210\u624d\u4f1a\u6267\u884c\u5b83\u3002\u800c\u5e38\u89c4\u811a\u672c\u5219\u4f1a\u7acb\u5373\u8fd0\u884c\uff0c\u6240\u4ee5\u6211\u4eec\u4f1a\u5148\u770b\u5230\u5e38\u89c4\u811a\u672c\u7684\u8f93\u51fa\u3002<br \/>\n\u5f53\u4f7f\u7528\u6a21\u5757\u811a\u672c\u65f6\uff0c\u6211\u4eec\u5e94\u8be5\u77e5\u9053 HTML \u9875\u9762\u5728\u52a0\u8f7d\u65f6\u5c31\u4f1a\u663e\u793a\u51fa\u6765\uff0c\u5728 HTML \u9875\u9762\u52a0\u8f7d\u5b8c\u6210\u540e\u624d\u4f1a\u6267\u884c JavaScript \u6a21\u5757\uff0c\u56e0\u6b64\u7528\u6237\u53ef\u80fd\u4f1a\u5728 JavaScript \u5e94\u7528\u7a0b\u5e8f\u51c6\u5907\u597d\u4e4b\u524d\u770b\u5230\u8be5\u9875\u9762\u3002\u67d0\u4e9b\u529f\u80fd\u53ef\u80fd\u8fd8\u65e0\u6cd5\u4f7f\u7528\u3002\u6211\u4eec\u5e94\u8be5\u653e\u7f6e\u201c\u52a0\u8f7d\u6307\u793a\u5668\uff08loading indicator\uff09\u201d\uff0c\u6216\u8005\u4ee5\u5176\u4ed6\u65b9\u5f0f\u786e\u4fdd\u8bbf\u95ee\u8005\u4e0d\u4f1a\u56e0\u6b64\u800c\u611f\u5230\u56f0\u60d1\u3002<\/p>\n<h3>Async \u9002\u7528\u4e8e\u5185\u8054\u811a\u672c\uff08inline script\uff09<\/h3>\n<p>\u5bf9\u4e8e\u975e\u6a21\u5757\u811a\u672c\uff0c<code>async<\/code>\u00a0\u7279\u6027\uff08attribute\uff09\u4ec5\u9002\u7528\u4e8e\u5916\u90e8\u811a\u672c\u3002\u5f02\u6b65\u811a\u672c\u4f1a\u5728\u51c6\u5907\u597d\u540e\u7acb\u5373\u8fd0\u884c\uff0c\u72ec\u7acb\u4e8e\u5176\u4ed6\u811a\u672c\u6216 HTML \u6587\u6863\u3002<br \/>\n\u5bf9\u4e8e\u6a21\u5757\u811a\u672c\uff0c\u5b83\u4e5f\u9002\u7528\u4e8e\u5185\u8054\u811a\u672c\u3002<br \/>\n\u4f8b\u5982\uff0c\u4e0b\u9762\u7684\u5185\u8054\u811a\u672c\u5177\u6709\u00a0<code>async<\/code>\u00a0\u7279\u6027\uff0c\u56e0\u6b64\u5b83\u4e0d\u4f1a\u7b49\u5f85\u4efb\u4f55\u4e1c\u897f\u3002<br \/>\n\u5b83\u6267\u884c\u5bfc\u5165\uff08fetch\u00a0<code>.\/analytics.js<\/code>\uff09\uff0c\u5e76\u5728\u5bfc\u5165\u5b8c\u6210\u65f6\u8fd0\u884c\uff0c\u5373\u4f7f HTML \u6587\u6863\u8fd8\u672a\u5b8c\u6210\uff0c\u6216\u8005\u5176\u4ed6\u811a\u672c\u4ecd\u5728\u7b49\u5f85\u5904\u7406\u4e2d\u3002<br \/>\n\u8fd9\u5bf9\u4e8e\u4e0d\u4f9d\u8d56\u4efb\u4f55\u5176\u4ed6\u4e1c\u897f\u7684\u529f\u80fd\u6765\u8bf4\u662f\u975e\u5e38\u68d2\u7684\uff0c\u4f8b\u5982\u8ba1\u6570\u5668\uff0c\u5e7f\u544a\uff0c\u6587\u6863\u7ea7\u4e8b\u4ef6\u76d1\u542c\u5668\u3002<\/p>\n<pre><code class=\"language-html\">&lt;!-- \u6240\u6709\u4f9d\u8d56\u90fd\u83b7\u53d6\u5b8c\u6210\uff08analytics.js\uff09\u7136\u540e\u811a\u672c\u5f00\u59cb\u8fd0\u884c --&gt;\n&lt;!-- \u4e0d\u4f1a\u7b49\u5f85 HTML \u6587\u6863\u6216\u8005\u5176\u4ed6 &lt;script&gt; \u6807\u7b7e --&gt;\n&lt;script async type=&quot;module&quot;&gt;\n  import {counter} from '.\/analytics.js';\n\n  counter.count();\n&lt;\/script&gt;\n<\/code><\/pre>\n<h3>\u5916\u90e8\u811a\u672c<\/h3>\n<p>\u5177\u6709\u00a0<code>type=&quot;module&quot;<\/code>\u00a0\u7684\u5916\u90e8\u811a\u672c\uff08external script\uff09\u5728\u4e24\u4e2a\u65b9\u9762\u6709\u6240\u4e0d\u540c\uff1a<\/p>\n<ol>\n<li>\u5177\u6709\u76f8\u540c\u00a0<code>src<\/code>\u00a0\u7684\u5916\u90e8\u811a\u672c\u4ec5\u8fd0\u884c\u4e00\u6b21\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-html\">&lt;!-- \u811a\u672c my.js \u88ab\u52a0\u8f7d\u5b8c\u6210\uff08fetched\uff09\u5e76\u53ea\u88ab\u8fd0\u884c\u4e00\u6b21 --&gt;\n&lt;script type=&quot;module&quot; src=&quot;my.js&quot;&gt;&lt;\/script&gt;\n&lt;script type=&quot;module&quot; src=&quot;my.js&quot;&gt;&lt;\/script&gt;\n<\/code><\/pre>\n<ol start=\"2\">\n<li>\u4ece\u53e6\u4e00\u4e2a\u6e90\uff08\u4f8b\u5982\u53e6\u4e00\u4e2a\u7f51\u7ad9\uff09\u83b7\u53d6\u7684\u5916\u90e8\u811a\u672c\u9700\u8981\u00a0<a href=\"https:\/\/developer.mozilla.org\/zh\/docs\/Web\/HTTP\/CORS\">CORS<\/a>\u00a0header\uff0c\u5982\u6211\u4eec\u5728\u00a0<a href=\"https:\/\/zh.javascript.info\/fetch-crossorigin\">Fetch\uff1a\u8de8\u6e90\u8bf7\u6c42<\/a>\u00a0\u4e00\u7ae0\u4e2d\u6240\u8bb2\u7684\u90a3\u6837\u3002\u6362\u53e5\u8bdd\u8bf4\uff0c\u5982\u679c\u4e00\u4e2a\u6a21\u5757\u811a\u672c\u662f\u4ece\u53e6\u4e00\u4e2a\u6e90\u83b7\u53d6\u7684\uff0c\u5219\u8fdc\u7a0b\u670d\u52a1\u5668\u5fc5\u987b\u63d0\u4f9b\u8868\u793a\u5141\u8bb8\u83b7\u53d6\u7684 header\u00a0<code>Access-Control-Allow-Origin<\/code>\u3002<\/li>\n<\/ol>\n<pre><code class=\"language-html\">&lt;!-- another-site.com \u5fc5\u987b\u63d0\u4f9b Access-Control-Allow-Origin --&gt;\n&lt;!-- \u5426\u5219\uff0c\u811a\u672c\u5c06\u65e0\u6cd5\u6267\u884c --&gt;\n&lt;script type=&quot;module&quot; src=&quot;http:\/\/another-site.com\/their.js&quot;&gt;&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u9ed8\u8ba4\u8fd9\u6837\u505a\u53ef\u4ee5\u786e\u4fdd\u66f4\u597d\u7684\u5b89\u5168\u6027\u3002<\/p>\n<h3>\u4e0d\u5141\u8bb8\u88f8\u6a21\u5757 \uff08&quot;bare&quot; module\uff09<\/h3>\n<p>\u5728\u6d4f\u89c8\u5668\u4e2d\uff0c<code>import<\/code>\u00a0\u5fc5\u987b\u7ed9\u51fa\u76f8\u5bf9\u6216\u7edd\u5bf9\u7684 URL \u8def\u5f84\u3002\u6ca1\u6709\u4efb\u4f55\u8def\u5f84\u7684\u6a21\u5757\u88ab\u79f0\u4e3a\u201c\u88f8\uff08bare\uff09\u201d\u6a21\u5757\u3002\u5728\u00a0<code>import<\/code>\u00a0\u4e2d\u4e0d\u5141\u8bb8\u8fd9\u79cd\u6a21\u5757\u3002<br \/>\n\u4f8b\u5982\uff0c\u4e0b\u9762\u8fd9\u4e2a\u00a0<code>import<\/code>\u00a0\u662f\u65e0\u6548\u7684\uff1a<\/p>\n<pre><code class=\"language-js\">import {sayHi} from 'sayHi'; \/\/ Error\uff0c\u201c\u88f8\u201d\u6a21\u5757\n\/\/ \u6a21\u5757\u5fc5\u987b\u6709\u4e00\u4e2a\u8def\u5f84\uff0c\u4f8b\u5982 '.\/sayHi.js' \u6216\u8005\u5176\u4ed6\u4efb\u4f55\u8def\u5f84\n<\/code><\/pre>\n<p>\u67d0\u4e9b\u73af\u5883\uff0c\u50cf Node.js \u6216\u8005\u6253\u5305\u5de5\u5177\uff08bundle tool\uff09\u5141\u8bb8\u6ca1\u6709\u4efb\u4f55\u8def\u5f84\u7684\u88f8\u6a21\u5757\uff0c\u56e0\u4e3a\u5b83\u4eec\u6709\u81ea\u5df1\u7684\u67e5\u627e\u6a21\u5757\u7684\u65b9\u6cd5\u548c\u94a9\u5b50\uff08hook\uff09\u6765\u5bf9\u5b83\u4eec\u8fdb\u884c\u5fae\u8c03\u3002\u4f46\u662f\u6d4f\u89c8\u5668\u5c1a\u4e0d\u652f\u6301\u88f8\u6a21\u5757\u3002<\/p>\n<h3>\u517c\u5bb9\u6027 nomodule<\/h3>\n<p>\u65e7\u65f6\u7684\u6d4f\u89c8\u5668\u4e0d\u7406\u89e3\u00a0<code>type=&quot;module&quot;<\/code>\u3002\u672a\u77e5\u7c7b\u578b\u7684\u811a\u672c\u4f1a\u88ab\u5ffd\u7565\u3002\u5bf9\u6b64\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>nomodule<\/code>\u00a0\u7279\u6027\u6765\u63d0\u4f9b\u4e00\u4e2a\u540e\u5907\uff1a<\/p>\n<pre><code class=\"language-html\">&lt;script type=&quot;module&quot;&gt;\n  alert(&quot;Runs in modern browsers&quot;);\n&lt;\/script&gt;\n\n&lt;script nomodule&gt;\n  alert(&quot;Modern browsers know both type=module and nomodule, so skip this&quot;)\n  alert(&quot;Old browsers ignore script with unknown type=module, but execute this.&quot;);\n&lt;\/script&gt;\n<\/code><\/pre>\n<h2>\u6784\u5efa\u5de5\u5177<\/h2>\n<p>\u5728\u5b9e\u9645\u5f00\u53d1\u4e2d\uff0c\u6d4f\u89c8\u5668\u6a21\u5757\u5f88\u5c11\u88ab\u4ee5\u201c\u539f\u59cb\u201d\u5f62\u5f0f\u8fdb\u884c\u4f7f\u7528\u3002\u901a\u5e38\uff0c\u6211\u4eec\u4f1a\u4f7f\u7528\u4e00\u4e9b\u7279\u6b8a\u5de5\u5177\uff0c\u4f8b\u5982\u00a0<a href=\"https:\/\/webpack.js.org\/\">Webpack<\/a>\uff0c\u5c06\u5b83\u4eec\u6253\u5305\u5728\u4e00\u8d77\uff0c\u7136\u540e\u90e8\u7f72\u5230\u751f\u4ea7\u73af\u5883\u7684\u670d\u52a1\u5668\u3002<br \/>\n\u4f7f\u7528\u6253\u5305\u5de5\u5177\u7684\u4e00\u4e2a\u597d\u5904\u662f \u2014\u2014 \u5b83\u4eec\u53ef\u4ee5\u66f4\u597d\u5730\u63a7\u5236\u6a21\u5757\u7684\u89e3\u6790\u65b9\u5f0f\uff0c\u5141\u8bb8\u6211\u4eec\u4f7f\u7528\u88f8\u6a21\u5757\u548c\u66f4\u591a\u7684\u529f\u80fd\uff0c\u4f8b\u5982 CSS\/HTML \u6a21\u5757\u7b49\u3002<br \/>\n\u6784\u5efa\u5de5\u5177\u505a\u4ee5\u4e0b\u8fd9\u4e9b\u4e8b\u513f\uff1a<\/p>\n<ol>\n<li>\u4ece\u4e00\u4e2a\u6253\u7b97\u653e\u5728 HTML \u4e2d\u7684\u00a0<code>&lt;script type=&quot;module&quot;&gt;<\/code>\u00a0\u201c\u4e3b\u201d\u6a21\u5757\u5f00\u59cb\u3002<\/li>\n<li>\u5206\u6790\u5b83\u7684\u4f9d\u8d56\uff1a\u5b83\u7684\u5bfc\u5165\uff0c\u4ee5\u53ca\u5b83\u7684\u5bfc\u5165\u7684\u5bfc\u5165\u7b49\u3002<\/li>\n<li>\u4f7f\u7528\u6240\u6709\u6a21\u5757\u6784\u5efa\u4e00\u4e2a\u6587\u4ef6\uff08\u6216\u8005\u591a\u4e2a\u6587\u4ef6\uff0c\u8fd9\u662f\u53ef\u8c03\u7684\uff09\uff0c\u5e76\u7528\u6253\u5305\u51fd\u6570\uff08bundler function\uff09\u66ff\u4ee3\u539f\u751f\u7684\u00a0<code>import<\/code>\u00a0\u8c03\u7528\uff0c\u4ee5\u4f7f\u5176\u6b63\u5e38\u5de5\u4f5c\u3002\u8fd8\u652f\u6301\u50cf HTML\/CSS \u6a21\u5757\u7b49\u201c\u7279\u6b8a\u201d\u7684\u6a21\u5757\u7c7b\u578b\u3002<\/li>\n<li>\u5728\u5904\u7406\u8fc7\u7a0b\u4e2d\uff0c\u53ef\u80fd\u4f1a\u5e94\u7528\u5176\u4ed6\u8f6c\u6362\u548c\u4f18\u5316\uff1a\n<ul>\n<li>\u5220\u9664\u65e0\u6cd5\u8bbf\u95ee\u7684\u4ee3\u7801\u3002<\/li>\n<li>\u5220\u9664\u672a\u4f7f\u7528\u7684\u5bfc\u51fa\uff08\u201ctree-shaking\u201d\uff09\u3002<\/li>\n<li>\u5220\u9664\u7279\u5b9a\u4e8e\u5f00\u53d1\u7684\u50cf\u00a0<code>console<\/code>\u00a0\u548c\u00a0<code>debugger<\/code>\u00a0\u8fd9\u6837\u7684\u8bed\u53e5\u3002<\/li>\n<li>\u53ef\u4ee5\u4f7f\u7528\u00a0<a href=\"https:\/\/babeljs.io\/\">Babel<\/a>\u00a0\u5c06\u524d\u6cbf\u7684\u73b0\u4ee3\u7684 JavaScript \u8bed\u6cd5\u8f6c\u6362\u4e3a\u5177\u6709\u7c7b\u4f3c\u529f\u80fd\u7684\u65e7\u7684 JavaScript \u8bed\u6cd5\u3002<\/li>\n<li>\u538b\u7f29\u751f\u6210\u7684\u6587\u4ef6\uff08\u5220\u9664\u7a7a\u683c\uff0c\u7528\u77ed\u7684\u540d\u5b57\u66ff\u6362\u53d8\u91cf\u7b49\uff09\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u4f7f\u7528\u6253\u5305\u5de5\u5177\uff0c\u90a3\u4e48\u811a\u672c\u4f1a\u88ab\u6253\u5305\u8fdb\u4e00\u4e2a\u5355\u4e00\u6587\u4ef6\uff08\u6216\u8005\u51e0\u4e2a\u6587\u4ef6\uff09\uff0c\u5728\u8fd9\u4e9b\u811a\u672c\u4e2d\u7684\u00a0<code>import\/export<\/code>\u00a0\u8bed\u53e5\u4f1a\u88ab\u66ff\u6362\u6210\u7279\u6b8a\u7684\u6253\u5305\u51fd\u6570\uff08bundler function\uff09\u3002\u56e0\u6b64\uff0c\u6700\u7ec8\u6253\u5305\u597d\u7684\u811a\u672c\u4e2d\u4e0d\u5305\u542b\u4efb\u4f55\u00a0<code>import\/export<\/code>\uff0c\u5b83\u4e5f\u4e0d\u9700\u8981\u00a0<code>type=&quot;module&quot;<\/code>\uff0c\u6211\u4eec\u53ef\u4ee5\u5c06\u5176\u653e\u5165\u5e38\u89c4\u7684\u00a0<code>&lt;script&gt;<\/code>\uff1a<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<pre><code class=\"language-js\">&lt;!-- \u5047\u8bbe\u6211\u4eec\u4ece\u8bf8\u5982 Webpack \u8fd9\u7c7b\u7684\u6253\u5305\u5de5\u5177\u4e2d\u83b7\u5f97\u4e86 &quot;bundle.js&quot; \u811a\u672c --&gt;\n&lt;script src=&quot;bundle.js&quot;&gt;&lt;\/script&gt;\n<\/code><\/pre>\n<p>\u5173\u4e8e\u6784\u5efa\u5de5\u5177\u8bf4\u4e86\u8fd9\u4e48\u591a\uff0c\u4f46\u5176\u5b9e\u539f\u751f\u6a21\u5757\u4e5f\u662f\u53ef\u4ee5\u7528\u7684\u3002\u6240\u4ee5\uff0c\u6211\u4eec\u5728\u8fd9\u513f\u5c06\u4e0d\u4f1a\u4f7f\u7528 Webpack\uff1a\u4f60\u53ef\u4ee5\u7a0d\u540e\u518d\u914d\u7f6e\u5b83\u3002<\/p>\n<h1>\u5bfc\u5165\u548c\u5bfc\u51fa<\/h1>\n<p>\u5bfc\u51fa\uff08export\uff09\u548c\u5bfc\u5165\uff08import\uff09\u6307\u4ee4\u6709\u51e0\u79cd\u8bed\u6cd5\u53d8\u4f53\u3002<br \/>\n\u5728\u4e0a\u4e00\u8282\uff0c\u6211\u4eec\u770b\u5230\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u7528\u6cd5\uff0c\u73b0\u5728\u8ba9\u6211\u4eec\u6765\u63a2\u7d22\u66f4\u591a\u793a\u4f8b\u5427\u3002<\/p>\n<h2>\u5728\u58f0\u660e\u524d\u5bfc\u51fa<\/h2>\n<p>\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5728\u58f0\u660e\u4e4b\u524d\u653e\u7f6e\u00a0<code>export<\/code>\u00a0\u6765\u6807\u8bb0\u4efb\u610f\u58f0\u660e\u4e3a\u5bfc\u51fa\uff0c\u65e0\u8bba\u58f0\u660e\u7684\u662f\u53d8\u91cf\uff0c\u51fd\u6570\u8fd8\u662f\u7c7b\u90fd\u53ef\u4ee5\u3002<br \/>\n\u4f8b\u5982\uff0c\u8fd9\u91cc\u7684\u6240\u6709\u5bfc\u51fa\u5747\u6709\u6548\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \u5bfc\u51fa\u6570\u7ec4\nexport let months = ['Jan', 'Feb', 'Mar','Apr', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];\n\n\/\/ \u5bfc\u51fa const \u58f0\u660e\u7684\u53d8\u91cf\nexport const MODULES_BECAME_STANDARD_YEAR = 2015;\n\n\/\/ \u5bfc\u51fa\u7c7b\nexport class User {\n  constructor(name) {\n    this.name = name;\n  }\n}\n<\/code><\/pre>\n<blockquote>\n<p>\u5bfc\u51fa class\/function \u540e\u6ca1\u6709\u5206\u53f7<br \/>\n\u6ce8\u610f\uff0c\u5728\u7c7b\u6216\u8005\u51fd\u6570\u524d\u7684\u00a0<code>export<\/code>\u00a0\u4e0d\u4f1a\u8ba9\u5b83\u4eec\u53d8\u6210\u00a0<a href=\"https:\/\/zh.javascript.info\/function-expressions\">\u51fd\u6570\u8868\u8fbe\u5f0f<\/a>\u3002\u5c3d\u7ba1\u88ab\u5bfc\u51fa\u4e86\uff0c\u4f46\u5b83\u4ecd\u7136\u662f\u4e00\u4e2a\u51fd\u6570\u58f0\u660e\u3002<br \/>\n\u5927\u90e8\u5206 JavaScript \u6837\u5f0f\u6307\u5357\u90fd\u4e0d\u5efa\u8bae\u5728\u51fd\u6570\u548c\u7c7b\u58f0\u660e\u540e\u4f7f\u7528\u5206\u53f7\u3002<br \/>\n\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u5728\u00a0<code>export class<\/code>\u00a0\u548c\u00a0<code>export function<\/code>\u00a0\u7684\u672b\u5c3e\u4e0d\u9700\u8981\u52a0\u5206\u53f7\uff1a<\/p>\n<\/blockquote>\n<pre><code class=\"language-js\">export function sayHi(user) {\n  alert(`Hello, ${user}!`);\n}  \/\/ \u5728\u8fd9\u91cc\u6ca1\u6709\u5206\u53f7 ;\n<\/code><\/pre>\n<h2>\u5bfc\u51fa\u4e0e\u58f0\u660e\u5206\u5f00<\/h2>\n<p>\u53e6\u5916\uff0c\u6211\u4eec\u8fd8\u53ef\u4ee5\u5c06\u00a0<code>export<\/code>\u00a0\u5206\u5f00\u653e\u7f6e\u3002<br \/>\n\u4e0b\u9762\u7684\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u5148\u58f0\u660e\u51fd\u6570\uff0c\u7136\u540e\u518d\u5bfc\u51fa\u5b83\u4eec\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 say.js\nfunction sayHi(user) {\n  alert(`Hello, ${user}!`);\n}\n\nfunction sayBye(user) {\n  alert(`Bye, ${user}!`);\n}\n\nexport {sayHi, sayBye}; \/\/ \u5bfc\u51fa\u53d8\u91cf\u5217\u8868\n<\/code><\/pre>\n<p>\u2026\u2026\u4ece\u6280\u672f\u4e0a\u8bb2\uff0c\u6211\u4eec\u4e5f\u53ef\u4ee5\u628a\u00a0<code>export<\/code>\u00a0\u653e\u5728\u51fd\u6570\u4e0a\u9762\u3002<\/p>\n<h2>Import *<\/h2>\n<p>\u901a\u5e38\uff0c\u6211\u4eec\u628a\u8981\u5bfc\u5165\u7684\u4e1c\u897f\u5217\u5728\u82b1\u62ec\u53f7\u00a0<code>import {...}<\/code>\u00a0\u4e2d\uff0c\u5c31\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport {sayHi, sayBye} from '.\/say.js';\n\nsayHi('John'); \/\/ Hello, John!\nsayBye('John'); \/\/ Bye, John!\n<\/code><\/pre>\n<p>\u4f46\u662f\u5982\u679c\u6709\u5f88\u591a\u8981\u5bfc\u5165\u7684\u5185\u5bb9\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>import * as &lt;obj&gt;<\/code>\u00a0\u5c06\u6240\u6709\u5185\u5bb9\u5bfc\u5165\u4e3a\u4e00\u4e2a\u5bf9\u8c61\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport * as say from '.\/say.js';\n\nsay.sayHi('John');\nsay.sayBye('John');\n<\/code><\/pre>\n<p>\u4e4d\u4e00\u770b\uff0c\u201c\u901a\u901a\u5bfc\u5165\u201d\u770b\u8d77\u6765\u5f88\u9177\uff0c\u5199\u8d77\u6765\u4e5f\u5f88\u77ed\uff0c\u4f46\u662f\u6211\u4eec\u901a\u5e38\u4e3a\u4ec0\u4e48\u8981\u660e\u786e\u5217\u51fa\u6211\u4eec\u9700\u8981\u5bfc\u5165\u7684\u5185\u5bb9\uff1f<br \/>\n\u8fd9\u91cc\u6709\u51e0\u4e2a\u539f\u56e0\u3002<\/p>\n<ol>\n<li>\u73b0\u4ee3\u7684\u6784\u5efa\u5de5\u5177\uff08<a href=\"https:\/\/webpack.js.org\/\">webpack<\/a>\u00a0\u548c\u5176\u4ed6\u5de5\u5177\uff09\u5c06\u6a21\u5757\u6253\u5305\u5230\u4e00\u8d77\u5e76\u5bf9\u5176\u8fdb\u884c\u4f18\u5316\uff0c\u4ee5\u52a0\u5feb\u52a0\u8f7d\u901f\u5ea6\u5e76\u5220\u9664\u672a\u4f7f\u7528\u7684\u4ee3\u7801\u3002<br \/>\n\u6bd4\u5982\u8bf4\uff0c\u6211\u4eec\u5411\u6211\u4eec\u7684\u9879\u76ee\u91cc\u6dfb\u52a0\u4e00\u4e2a\u7b2c\u4e09\u65b9\u5e93\u00a0<code>say.js<\/code>\uff0c\u5b83\u5177\u6709\u8bb8\u591a\u51fd\u6570\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 say.js\nexport function sayHi() { ... }\nexport function sayBye() { ... }\nexport function becomeSilent() { ... }\n<\/code><\/pre>\n<p>\u73b0\u5728\uff0c\u5982\u679c\u6211\u4eec\u53ea\u5728\u6211\u4eec\u7684\u9879\u76ee\u91cc\u4f7f\u7528\u4e86\u00a0<code>say.js<\/code>\u00a0\u4e2d\u7684\u4e00\u4e2a\u51fd\u6570\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport {sayHi} from '.\/say.js';\n<\/code><\/pre>\n<p>\u2026\u2026\u90a3\u4e48\uff0c\u4f18\u5316\u5668\uff08optimizer\uff09\u5c31\u4f1a\u68c0\u6d4b\u5230\u5b83\uff0c\u5e76\u4ece\u6253\u5305\u597d\u7684\u4ee3\u7801\u4e2d\u5220\u9664\u90a3\u4e9b\u672a\u88ab\u4f7f\u7528\u7684\u51fd\u6570\uff0c\u4ece\u800c\u4f7f\u6784\u5efa\u66f4\u5c0f\u3002\u8fd9\u5c31\u662f\u6240\u8c13\u7684\u201c\u6447\u6811\uff08tree-shaking\uff09\u201d\u3002<br \/>\n2. \u660e\u786e\u5217\u51fa\u8981\u5bfc\u5165\u7684\u5185\u5bb9\u4f1a\u4f7f\u5f97\u540d\u79f0\u8f83\u77ed\uff1a<code>sayHi()<\/code>\u00a0\u800c\u4e0d\u662f\u00a0<code>say.sayHi()<\/code>\u3002<br \/>\n3. \u5bfc\u5165\u7684\u663e\u5f0f\u5217\u8868\u53ef\u4ee5\u66f4\u597d\u5730\u6982\u8ff0\u4ee3\u7801\u7ed3\u6784\uff1a\u4f7f\u7528\u7684\u5185\u5bb9\u548c\u4f4d\u7f6e\u3002\u5b83\u4f7f\u5f97\u4ee3\u7801\u652f\u6301\u91cd\u6784\uff0c\u5e76\u4e14\u91cd\u6784\u8d77\u6765\u66f4\u5bb9\u6613\u3002<\/p>\n<h2>Import &quot;as&quot;<\/h2>\n<p>\u6211\u4eec\u4e5f\u53ef\u4ee5\u4f7f\u7528\u00a0<code>as<\/code>\u00a0\u8ba9\u5bfc\u5165\u5177\u6709\u4e0d\u540c\u7684\u540d\u5b57\u3002<br \/>\n\u4f8b\u5982\uff0c\u7b80\u6d01\u8d77\u89c1\uff0c\u6211\u4eec\u5c06\u00a0<code>sayHi<\/code>\u00a0\u5bfc\u5165\u5230\u5c40\u90e8\u53d8\u91cf\u00a0<code>hi<\/code>\uff0c\u5c06\u00a0<code>sayBye<\/code>\u00a0\u5bfc\u5165\u5230\u00a0<code>bye<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport {sayHi as hi, sayBye as bye} from '.\/say.js';\n\nhi('John'); \/\/ Hello, John!\nbye('John'); \/\/ Bye, John!\n<\/code><\/pre>\n<h2>Export &quot;as&quot;<\/h2>\n<p>\u5bfc\u51fa\u4e5f\u5177\u6709\u7c7b\u4f3c\u7684\u8bed\u6cd5\u3002<br \/>\n\u6211\u4eec\u5c06\u51fd\u6570\u5bfc\u51fa\u4e3a\u00a0<code>hi<\/code>\u00a0\u548c\u00a0<code>bye<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 say.js\n...\nexport {sayHi as hi, sayBye as bye};\n<\/code><\/pre>\n<p>\u73b0\u5728\u00a0<code>hi<\/code>\u00a0\u548c\u00a0<code>bye<\/code>\u00a0\u662f\u5728\u5916\u9762\u4f7f\u7528\u65f6\u7684\u6b63\u5f0f\u540d\u79f0\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport * as say from '.\/say.js';\n\nsay.hi('John'); \/\/ Hello, John!\nsay.bye('John'); \/\/ Bye, John!\n<\/code><\/pre>\n<h2>Export default<\/h2>\n<p>\u5728\u5b9e\u9645\u4e2d\uff0c\u4e3b\u8981\u6709\u4e24\u79cd\u6a21\u5757\u3002<\/p>\n<ul>\n<li>\u5305\u542b\u5e93\u6216\u51fd\u6570\u5305\u7684\u6a21\u5757\uff0c\u50cf\u4e0a\u9762\u7684\u00a0<code>say.js<\/code>\u3002<\/li>\n<li>\u58f0\u660e\u5355\u4e2a\u5b9e\u4f53\u7684\u6a21\u5757\uff0c\u4f8b\u5982\u6a21\u5757\u00a0<code>user.js<\/code>\u00a0\u4ec5\u5bfc\u51fa\u00a0<code>class User<\/code>\u3002<br \/>\n\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\uff0c\u5f00\u53d1\u8005\u503e\u5411\u4e8e\u4f7f\u7528\u7b2c\u4e8c\u79cd\u65b9\u5f0f\uff0c\u4ee5\u4fbf\u6bcf\u4e2a\u201c\u4e1c\u897f\u201d\u90fd\u5b58\u5728\u4e8e\u5b83\u81ea\u5df1\u7684\u6a21\u5757\u4e2d\u3002<br \/>\n\u5f53\u7136\uff0c\u8fd9\u9700\u8981\u5927\u91cf\u6587\u4ef6\uff0c\u56e0\u4e3a\u6bcf\u4e2a\u4e1c\u897f\u90fd\u9700\u8981\u81ea\u5df1\u7684\u6a21\u5757\uff0c\u4f46\u8fd9\u6839\u672c\u4e0d\u662f\u95ee\u9898\u3002\u5b9e\u9645\u4e0a\uff0c\u5982\u679c\u6587\u4ef6\u5177\u6709\u826f\u597d\u7684\u547d\u540d\uff0c\u5e76\u4e14\u6587\u4ef6\u5939\u7ed3\u6784\u5f97\u5f53\uff0c\u90a3\u4e48\u4ee3\u7801\u5bfc\u822a\uff08navigation\uff09\u4f1a\u53d8\u5f97\u66f4\u5bb9\u6613\u3002<br \/>\n\u6a21\u5757\u63d0\u4f9b\u4e86\u4e00\u4e2a\u7279\u6b8a\u7684\u9ed8\u8ba4\u5bfc\u51fa\u00a0<code>export default<\/code>\u00a0\u8bed\u6cd5\uff0c\u4ee5\u4f7f\u201c\u4e00\u4e2a\u6a21\u5757\u53ea\u505a\u4e00\u4ef6\u4e8b\u201d\u7684\u65b9\u5f0f\u770b\u8d77\u6765\u66f4\u597d\u3002<br \/>\n\u5c06\u00a0<code>export default<\/code>\u00a0\u653e\u5728\u8981\u5bfc\u51fa\u7684\u5b9e\u4f53\u524d\uff1a<\/li>\n<\/ul>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 user.js\nexport default class User { \/\/ \u53ea\u9700\u8981\u6dfb\u52a0 &quot;default&quot; \u5373\u53ef\n  constructor(name) {\n    this.name = name;\n  }\n}\n<\/code><\/pre>\n<p>\u6bcf\u4e2a\u6587\u4ef6\u5e94\u8be5\u53ea\u6709\u4e00\u4e2a\u00a0<code>export default<\/code>\uff1a<br \/>\n\u2026\u2026\u7136\u540e\u5c06\u5176\u5bfc\u5165\u800c\u4e0d\u9700\u8981\u82b1\u62ec\u53f7\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport User from '.\/user.js'; \/\/ \u4e0d\u9700\u8981\u82b1\u62ec\u53f7 {User}\uff0c\u53ea\u9700\u8981\u5199\u6210 User \u5373\u53ef\n\nnew User('John');\n<\/code><\/pre>\n<p>\u4e0d\u7528\u82b1\u62ec\u53f7\u7684\u5bfc\u5165\u770b\u8d77\u6765\u5f88\u9177\u3002\u521a\u5f00\u59cb\u4f7f\u7528\u6a21\u5757\u65f6\uff0c\u4e00\u4e2a\u5e38\u89c1\u7684\u9519\u8bef\u5c31\u662f\u5fd8\u8bb0\u5199\u82b1\u62ec\u53f7\u3002\u6240\u4ee5\uff0c\u8bf7\u8bb0\u4f4f\uff0c<code>import<\/code>\u00a0\u547d\u540d\u7684\u5bfc\u51fa\u65f6\u9700\u8981\u82b1\u62ec\u53f7\uff0c\u800c\u00a0<code>import<\/code>\u00a0\u9ed8\u8ba4\u7684\u5bfc\u51fa\u65f6\u4e0d\u9700\u8981\u82b1\u62ec\u53f7\u3002<\/p>\n<table>\n<thead>\n<tr>\n<th>\u547d\u540d\u7684\u5bfc\u51fa<\/th>\n<th>\u9ed8\u8ba4\u7684\u5bfc\u51fa<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><code>export class User {...}<\/code><\/td>\n<td><code>export default class User {...}<\/code><\/td>\n<\/tr>\n<tr>\n<td><code>import {User} from ...<\/code><\/td>\n<td><code>import User from ...<\/code><\/td>\n<\/tr>\n<tr>\n<td>\u4ece\u6280\u672f\u4e0a\u8bb2\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u4e00\u4e2a\u6a21\u5757\u4e2d\u540c\u65f6\u6709\u9ed8\u8ba4\u7684\u5bfc\u51fa\u548c\u547d\u540d\u7684\u5bfc\u51fa\uff0c\u4f46\u662f\u5b9e\u9645\u4e0a\u4eba\u4eec\u901a\u5e38\u4e0d\u4f1a\u6df7\u5408\u4f7f\u7528\u5b83\u4eec\u3002\u6a21\u5757\u8981\u4e48\u662f\u547d\u540d\u7684\u5bfc\u51fa\u8981\u4e48\u662f\u9ed8\u8ba4\u7684\u5bfc\u51fa\u3002<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>\u7531\u4e8e\u6bcf\u4e2a\u6587\u4ef6\u6700\u591a\u53ea\u80fd\u6709\u4e00\u4e2a\u9ed8\u8ba4\u7684\u5bfc\u51fa\uff0c\u56e0\u6b64\u5bfc\u51fa\u7684\u5b9e\u4f53\u53ef\u80fd\u6ca1\u6709\u540d\u79f0\u3002<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>\u4f8b\u5982\uff0c\u4e0b\u9762\u8fd9\u4e9b\u90fd\u662f\u5b8c\u5168\u6709\u6548\u7684\u9ed8\u8ba4\u7684\u5bfc\u51fa\uff1a<\/td>\n<td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-js\">export default class { \/\/ \u6ca1\u6709\u7c7b\u540d\n  constructor() { ... }\n}\n\nexport default function(user) { \/\/ \u6ca1\u6709\u51fd\u6570\u540d\n  alert(`Hello, ${user}!`);\n}\n\n\/\/ \u5bfc\u51fa\u5355\u4e2a\u503c\uff0c\u800c\u4e0d\u4f7f\u7528\u53d8\u91cf\nexport default ['Jan', 'Feb', 'Mar','Apr', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];\n<\/code><\/pre>\n<p>\u4e0d\u6307\u5b9a\u540d\u79f0\u662f\u53ef\u4ee5\u7684\uff0c\u56e0\u4e3a\u6bcf\u4e2a\u6587\u4ef6\u53ea\u6709\u4e00\u4e2a\u00a0<code>export default<\/code>\uff0c\u56e0\u6b64\u4e0d\u5e26\u82b1\u62ec\u53f7\u7684\u00a0<code>import<\/code>\u00a0\u77e5\u9053\u8981\u5bfc\u5165\u7684\u5185\u5bb9\u662f\u4ec0\u4e48\u3002<br \/>\n\u5982\u679c\u6ca1\u6709\u00a0<code>default<\/code>\uff0c\u8fd9\u6837\u7684\u5bfc\u51fa\u5c06\u4f1a\u51fa\u9519\uff1a<\/p>\n<pre><code class=\"language-js\">export class { \/\/ Error!\uff08\u975e\u9ed8\u8ba4\u7684\u5bfc\u51fa\u9700\u8981\u540d\u79f0\uff09\n  constructor() {}\n}\n<\/code><\/pre>\n<h3>&quot;default&quot; \u540d\u79f0<\/h3>\n<p>\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c<code>default<\/code>\u00a0\u5173\u952e\u8bcd\u88ab\u7528\u4e8e\u5f15\u7528\u9ed8\u8ba4\u7684\u5bfc\u51fa\u3002<br \/>\n\u4f8b\u5982\uff0c\u8981\u5c06\u51fd\u6570\u4e0e\u5176\u5b9a\u4e49\u5206\u5f00\u5bfc\u51fa\uff1a<\/p>\n<pre><code class=\"language-js\">function sayHi(user) {\n  alert(`Hello, ${user}!`);\n}\n\n\/\/ \u5c31\u50cf\u6211\u4eec\u5728\u51fd\u6570\u4e4b\u524d\u6dfb\u52a0\u4e86 &quot;export default&quot; \u4e00\u6837\nexport {sayHi as default};\n<\/code><\/pre>\n<p>\u6216\u8005\uff0c\u53e6\u4e00\u79cd\u60c5\u51b5\uff0c\u5047\u8bbe\u6a21\u5757\u00a0<code>user.js<\/code>\u00a0\u5bfc\u51fa\u4e86\u4e00\u4e2a\u4e3b\u8981\u7684\u9ed8\u8ba4\u7684\u5bfc\u51fa\u548c\u4e00\u4e9b\u547d\u540d\u7684\u5bfc\u51fa\uff08\u8fd9\u79cd\u60c5\u51b5\u5f88\u5c11\u89c1\uff0c\u4f46\u786e\u5b9e\u4f1a\u53d1\u751f\uff09\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 user.js\nexport default class User {\n  constructor(name) {\n    this.name = name;\n  }\n}\n\nexport function sayHi(user) {\n  alert(`Hello, ${user}!`);\n}\n<\/code><\/pre>\n<p>\u8fd9\u662f\u5bfc\u5165\u9ed8\u8ba4\u7684\u5bfc\u51fa\u4ee5\u53ca\u547d\u540d\u7684\u5bfc\u51fa\u7684\u65b9\u6cd5\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport {default as User, sayHi} from '.\/user.js';\n\nnew User('John');\n<\/code><\/pre>\n<p>\u5982\u679c\u6211\u4eec\u5c06\u6240\u6709\u4e1c\u897f\u00a0<code>*<\/code>\u00a0\u4f5c\u4e3a\u4e00\u4e2a\u5bf9\u8c61\u5bfc\u5165\uff0c\u90a3\u4e48\u00a0<code>default<\/code>\u00a0\u5c5e\u6027\u6b63\u662f\u9ed8\u8ba4\u7684\u5bfc\u51fa\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 main.js\nimport * as user from '.\/user.js';\n\nlet User = user.default; \/\/ \u9ed8\u8ba4\u7684\u5bfc\u51fa\nnew User('John');\n<\/code><\/pre>\n<h3>\u5e94\u8be5\u4f7f\u7528\u9ed8\u8ba4\u7684\u5bfc\u51fa\u5417<\/h3>\n<p>\u547d\u540d\u7684\u5bfc\u51fa\u662f\u660e\u786e\u7684\u3002\u5b83\u4eec\u786e\u5207\u5730\u547d\u540d\u4e86\u5b83\u4eec\u8981\u5bfc\u51fa\u7684\u5185\u5bb9\uff0c\u56e0\u6b64\u6211\u4eec\u80fd\u4ece\u5b83\u4eec\u83b7\u5f97\u8fd9\u4e9b\u4fe1\u606f\uff0c\u8fd9\u662f\u4e00\u4ef6\u597d\u4e8b\u3002<br \/>\n\u547d\u540d\u7684\u5bfc\u51fa\u4f1a\u5f3a\u5236\u6211\u4eec\u4f7f\u7528\u6b63\u786e\u7684\u540d\u79f0\u8fdb\u884c\u5bfc\u5165\uff1a<\/p>\n<pre><code class=\"language-js\">import {User} from '.\/user.js';\n\/\/ \u5bfc\u5165 {MyUser} \u4e0d\u8d77\u4f5c\u7528\uff0c\u5bfc\u5165\u540d\u5b57\u5fc5\u987b\u4e3a {User}\n<\/code><\/pre>\n<p>\u2026\u2026\u5bf9\u4e8e\u9ed8\u8ba4\u7684\u5bfc\u51fa\uff0c\u6211\u4eec\u603b\u662f\u5728\u5bfc\u5165\u65f6\u9009\u62e9\u540d\u79f0\uff1a<\/p>\n<pre><code class=\"language-js\">import User from '.\/user.js'; \/\/ \u6709\u6548\nimport MyUser from '.\/user.js'; \/\/ \u4e5f\u6709\u6548\n\/\/ \u4f7f\u7528\u4efb\u4f55\u540d\u79f0\u5bfc\u5165\u90fd\u6ca1\u6709\u95ee\u9898\n<\/code><\/pre>\n<p>\u56e0\u6b64\uff0c\u56e2\u961f\u6210\u5458\u53ef\u80fd\u4f1a\u4f7f\u7528\u4e0d\u540c\u7684\u540d\u79f0\u6765\u5bfc\u5165\u76f8\u540c\u7684\u5185\u5bb9\uff0c\u8fd9\u4e0d\u597d\u3002<br \/>\n\u901a\u5e38\uff0c\u4e3a\u4e86\u907f\u514d\u8fd9\u79cd\u60c5\u51b5\u5e76\u4f7f\u4ee3\u7801\u4fdd\u6301\u4e00\u81f4\uff0c\u53ef\u4ee5\u9075\u4ece\u8fd9\u6761\u89c4\u5219\uff0c\u5373\u5bfc\u5165\u7684\u53d8\u91cf\u5e94\u4e0e\u6587\u4ef6\u540d\u76f8\u5bf9\u5e94\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">import User from '.\/user.js';\nimport LoginForm from '.\/loginForm.js';\nimport func from '\/path\/to\/func.js';\n...\n<\/code><\/pre>\n<p>\u4f46\u662f\uff0c\u4e00\u4e9b\u56e2\u961f\u4ecd\u7136\u8ba4\u4e3a\u8fd9\u662f\u9ed8\u8ba4\u7684\u5bfc\u51fa\u7684\u4e25\u91cd\u7f3a\u9677\u3002\u56e0\u6b64\uff0c\u4ed6\u4eec\u66f4\u503e\u5411\u4e8e\u59cb\u7ec8\u4f7f\u7528\u547d\u540d\u7684\u5bfc\u51fa\u3002\u5373\u4f7f\u53ea\u5bfc\u51fa\u4e00\u4e2a\u4e1c\u897f\uff0c\u4e5f\u4ecd\u7136\u4f7f\u7528\u547d\u540d\u7684\u5bfc\u51fa\uff0c\u800c\u4e0d\u662f\u9ed8\u8ba4\u7684\u5bfc\u51fa\u3002<br \/>\n\u8fd9\u4e5f\u4f7f\u5f97\u91cd\u65b0\u5bfc\u51fa\uff08\u89c1\u4e0b\u6587\uff09\u66f4\u5bb9\u6613\u3002<\/p>\n<h2>\u91cd\u65b0\u5bfc\u51fa<\/h2>\n<p>\u201c\u91cd\u65b0\u5bfc\u51fa\uff08Re-export\uff09\u201d\u8bed\u6cd5\u00a0<code>export ... from ...<\/code>\u00a0\u5141\u8bb8\u5bfc\u5165\u5185\u5bb9\uff0c\u5e76\u7acb\u5373\u5c06\u5176\u5bfc\u51fa\uff08\u53ef\u80fd\u662f\u7528\u7684\u662f\u5176\u4ed6\u7684\u540d\u5b57\uff09\uff0c\u5c31\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">export {sayHi} from '.\/say.js'; \/\/ \u91cd\u65b0\u5bfc\u51fa sayHi\n\nexport {default as User} from '.\/user.js'; \/\/ \u91cd\u65b0\u5bfc\u51fa default\n<\/code><\/pre>\n<p>\u4e3a\u4ec0\u4e48\u8981\u8fd9\u6837\u505a\uff1f\u6211\u4eec\u770b\u4e00\u4e2a\u5b9e\u9645\u5f00\u53d1\u4e2d\u7684\u7528\u4f8b\u3002<br \/>\n\u60f3\u8c61\u4e00\u4e0b\uff0c\u6211\u4eec\u6b63\u5728\u7f16\u5199\u4e00\u4e2a \u201cpackage\u201d\uff1a\u4e00\u4e2a\u5305\u542b\u5927\u91cf\u6a21\u5757\u7684\u6587\u4ef6\u5939\uff0c\u5176\u4e2d\u4e00\u4e9b\u529f\u80fd\u662f\u5bfc\u51fa\u5230\u5916\u90e8\u7684\uff08\u50cf NPM \u8fd9\u6837\u7684\u5de5\u5177\u5141\u8bb8\u6211\u4eec\u53d1\u5e03\u548c\u5206\u53d1\u8fd9\u6837\u7684 package\uff0c\u4f46\u6211\u4eec\u4e0d\u662f\u5fc5\u987b\u8981\u53bb\u4f7f\u7528\u5b83\u4eec\uff09\uff0c\u5e76\u4e14\u5176\u4e2d\u4e00\u4e9b\u6a21\u5757\u4ec5\u4ec5\u662f\u4f9b\u5176\u4ed6 package \u4e2d\u7684\u6a21\u5757\u5185\u90e8\u4f7f\u7528\u7684 \u201chelpers\u201d\u3002<br \/>\n\u6587\u4ef6\u7ed3\u6784\u53ef\u80fd\u662f\u8fd9\u6837\u7684\uff1a<\/p>\n<pre><code class=\"language-FileStruct\">auth\/\n    index.js\n    user.js\n    helpers.js\n    tests\/\n        login.js\n    providers\/\n        github.js\n        facebook.js\n        ...\n<\/code><\/pre>\n<p>\u6211\u4eec\u5e0c\u671b\u901a\u8fc7\u5355\u4e2a\u5165\u53e3\u66b4\u9732\u5305\u7684\u529f\u80fd\u3002<br \/>\n\u6362\u53e5\u8bdd\u8bf4\uff0c\u60f3\u8981\u4f7f\u7528\u6211\u4eec\u7684\u5305\u7684\u4eba\uff0c\u5e94\u8be5\u53ea\u4ece\u201c\u4e3b\u6587\u4ef6\u201d\u00a0<code>auth\/index.js<\/code>\u00a0\u5bfc\u5165\u3002<br \/>\n\u50cf\u8fd9\u6837\uff1a<\/p>\n<pre><code class=\"language-js\">import {login, logout} from 'auth\/index.js'\n<\/code><\/pre>\n<p>\u201c\u4e3b\u6587\u4ef6\u201d\uff0c<code>auth\/index.js<\/code>\u00a0\u5bfc\u51fa\u4e86\u6211\u4eec\u5e0c\u671b\u5728\u5305\u4e2d\u63d0\u4f9b\u7684\u6240\u6709\u529f\u80fd\u3002<br \/>\n\u8fd9\u6837\u505a\u662f\u56e0\u4e3a\uff0c\u5176\u4ed6\u4f7f\u7528\u6211\u4eec\u5305\u7684\u5f00\u53d1\u8005\u4e0d\u5e94\u8be5\u5e72\u9884\u5176\u5185\u90e8\u7ed3\u6784\uff0c\u4e0d\u5e94\u8be5\u641c\u7d22\u6211\u4eec\u5305\u7684\u6587\u4ef6\u5939\u4e2d\u7684\u6587\u4ef6\u3002\u6211\u4eec\u53ea\u5728\u00a0<code>auth\/index.js<\/code>\u00a0\u4e2d\u5bfc\u51fa\u5fc5\u8981\u7684\u90e8\u5206\uff0c\u5e76\u4fdd\u6301\u5176\u4ed6\u5185\u5bb9\u201c\u4e0d\u53ef\u89c1\u201d\u3002<br \/>\n\u7531\u4e8e\u5b9e\u9645\u5bfc\u51fa\u7684\u529f\u80fd\u5206\u6563\u5728 package \u4e2d\uff0c\u6240\u4ee5\u6211\u4eec\u53ef\u4ee5\u5c06\u5b83\u4eec\u5bfc\u5165\u5230\u00a0<code>auth\/index.js<\/code>\uff0c\u7136\u540e\u518d\u4ece\u4e2d\u5bfc\u51fa\u5b83\u4eec\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 auth\/index.js\n\n\/\/ \u5bfc\u5165 login\/logout \u7136\u540e\u7acb\u5373\u5bfc\u51fa\u5b83\u4eec\nimport {login, logout} from '.\/helpers.js';\nexport {login, logout};\n\n\/\/ \u5c06\u9ed8\u8ba4\u5bfc\u51fa\u5bfc\u5165\u4e3a User\uff0c\u7136\u540e\u5bfc\u51fa\u5b83\nimport User from '.\/user.js';\nexport {User};\n...\n<\/code><\/pre>\n<p>\u73b0\u5728\u4f7f\u7528\u6211\u4eec package \u7684\u4eba\u53ef\u4ee5\u00a0<code>import {login} from &quot;auth\/index.js&quot;<\/code>\u3002<br \/>\n\u8bed\u6cd5\u00a0<code>export ... from ...<\/code>\u00a0\u53ea\u662f\u4e0a\u9762\u8fd9\u79cd\u5bfc\u5165-\u5bfc\u51fa\u7684\u7b80\u5199\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 auth\/index.js\n\/\/ \u91cd\u65b0\u5bfc\u51fa login\/logout\nexport {login, logout} from '.\/helpers.js';\n\n\/\/ \u5c06\u9ed8\u8ba4\u5bfc\u51fa\u91cd\u65b0\u5bfc\u51fa\u4e3a User\nexport {default as User} from '.\/user.js';\n...\n<\/code><\/pre>\n<p><code>export ... from<\/code>\u00a0\u4e0e\u00a0<code>import\/export<\/code>\u00a0\u76f8\u6bd4\u7684\u663e\u7740\u533a\u522b\u662f\u91cd\u65b0\u5bfc\u51fa\u7684\u6a21\u5757\u5728\u5f53\u524d\u6587\u4ef6\u4e2d\u4e0d\u53ef\u7528\u3002\u6240\u4ee5\u5728\u4e0a\u9762\u7684\u00a0<code>auth\/index.js<\/code>\u00a0\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u4e0d\u80fd\u4f7f\u7528\u91cd\u65b0\u5bfc\u51fa\u7684\u00a0<code>login\/logout<\/code>\u00a0\u51fd\u6570\u3002<\/p>\n<h3>\u91cd\u65b0\u5bfc\u51fa\u9ed8\u8ba4\u5bfc\u51fa<\/h3>\n<p>\u91cd\u65b0\u5bfc\u51fa\u65f6\uff0c\u9ed8\u8ba4\u5bfc\u51fa\u9700\u8981\u5355\u72ec\u5904\u7406\u3002<br \/>\n\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u00a0<code>user.js<\/code>\u00a0\u811a\u672c\uff0c\u5176\u4e2d\u5199\u4e86\u00a0<code>export default class User<\/code>\uff0c\u5e76\u4e14\u6211\u4eec\u60f3\u91cd\u65b0\u5bfc\u51fa\u7c7b\u00a0<code>User<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 user.js\nexport default class User {\n  \/\/ ...\n}\n<\/code><\/pre>\n<p>\u6211\u4eec\u53ef\u80fd\u4f1a\u9047\u5230\u4e24\u4e2a\u95ee\u9898\uff1a<\/p>\n<ol>\n<li><code>export User from '.\/user.js'<\/code>\u00a0\u65e0\u6548\u3002\u8fd9\u4f1a\u5bfc\u81f4\u4e00\u4e2a\u8bed\u6cd5\u9519\u8bef\u3002<br \/>\n\u8981\u91cd\u65b0\u5bfc\u51fa\u9ed8\u8ba4\u5bfc\u51fa\uff0c\u6211\u4eec\u5fc5\u987b\u660e\u786e\u5199\u51fa\u00a0<code>export {default as User}<\/code>\uff0c\u5c31\u50cf\u4e0a\u9762\u7684\u4f8b\u5b50\u4e2d\u90a3\u6837\u3002<\/li>\n<li><code>export * from '.\/user.js'<\/code>\u00a0\u91cd\u65b0\u5bfc\u51fa\u53ea\u5bfc\u51fa\u4e86\u547d\u540d\u7684\u5bfc\u51fa\uff0c\u4f46\u662f\u5ffd\u7565\u4e86\u9ed8\u8ba4\u7684\u5bfc\u51fa\u3002<br \/>\n\u5982\u679c\u6211\u4eec\u60f3\u5c06\u547d\u540d\u7684\u5bfc\u51fa\u548c\u9ed8\u8ba4\u7684\u5bfc\u51fa\u90fd\u91cd\u65b0\u5bfc\u51fa\uff0c\u90a3\u4e48\u9700\u8981\u4e24\u6761\u8bed\u53e5\uff1a<\/li>\n<\/ol>\n<pre><code class=\"language-js\">export * from '.\/user.js'; \/\/ \u91cd\u65b0\u5bfc\u51fa\u547d\u540d\u7684\u5bfc\u51fa\nexport {default} from '.\/user.js'; \/\/ \u91cd\u65b0\u5bfc\u51fa\u9ed8\u8ba4\u7684\u5bfc\u51fa\n<\/code><\/pre>\n<p>\u91cd\u65b0\u5bfc\u51fa\u4e00\u4e2a\u9ed8\u8ba4\u5bfc\u51fa\u7684\u8fd9\u79cd\u5947\u602a\u73b0\u8c61\uff0c\u662f\u67d0\u4e9b\u5f00\u53d1\u8005\u4e0d\u559c\u6b22\u9ed8\u8ba4\u5bfc\u51fa\uff0c\u800c\u662f\u559c\u6b22\u547d\u540d\u7684\u5bfc\u51fa\u7684\u539f\u56e0\u4e4b\u4e00\u3002<\/p>\n<h1>\u52a8\u6001\u5bfc\u5165<\/h1>\n<p>\u6211\u4eec\u5728\u524d\u9762\u7ae0\u8282\u4e2d\u4ecb\u7ecd\u7684\u5bfc\u51fa\u548c\u5bfc\u5165\u8bed\u53e5\u79f0\u4e3a\u201c\u9759\u6001\u201d\u5bfc\u5165\u3002\u8bed\u6cd5\u975e\u5e38\u7b80\u5355\u4e14\u4e25\u683c\u3002<br \/>\n\u9996\u5148\uff0c\u6211\u4eec\u4e0d\u80fd\u52a8\u6001\u751f\u6210\u00a0<code>import<\/code>\u00a0\u7684\u4efb\u4f55\u53c2\u6570\u3002<br \/>\n\u6a21\u5757\u8def\u5f84\u5fc5\u987b\u662f\u539f\u59cb\u7c7b\u578b\u5b57\u7b26\u4e32\uff0c\u4e0d\u80fd\u662f\u51fd\u6570\u8c03\u7528\uff0c\u4e0b\u9762\u8fd9\u6837\u7684\u00a0<code>import<\/code>\u00a0\u884c\u4e0d\u901a\uff1a<\/p>\n<pre><code class=\"language-js\">import ... from getModuleName(); \/\/ Error, only from &quot;string&quot; is allowed\n<\/code><\/pre>\n<p>\u5176\u6b21\uff0c\u6211\u4eec\u65e0\u6cd5\u6839\u636e\u6761\u4ef6\u6216\u8005\u5728\u8fd0\u884c\u65f6\u5bfc\u5165\uff1a<\/p>\n<pre><code class=\"language-js\">if(...) {\n  import ...; \/\/ Error, not allowed!\n}\n\n{\n  import ...; \/\/ Error, we can't put import in any block\n}\n<\/code><\/pre>\n<p>\u8fd9\u662f\u56e0\u4e3a\u00a0<code>import<\/code>\/<code>export<\/code>\u00a0\u65e8\u5728\u63d0\u4f9b\u4ee3\u7801\u7ed3\u6784\u7684\u4e3b\u5e72\u3002\u8fd9\u662f\u975e\u5e38\u597d\u7684\u4e8b\u513f\uff0c\u56e0\u4e3a\u8fd9\u6837\u4fbf\u4e8e\u5206\u6790\u4ee3\u7801\u7ed3\u6784\uff0c\u53ef\u4ee5\u6536\u96c6\u6a21\u5757\uff0c\u53ef\u4ee5\u4f7f\u7528\u7279\u6b8a\u5de5\u5177\u5c06\u6536\u96c6\u7684\u6a21\u5757\u6253\u5305\u5230\u4e00\u4e2a\u6587\u4ef6\u4e2d\uff0c\u53ef\u4ee5\u5220\u9664\u672a\u4f7f\u7528\u7684\u5bfc\u51fa\uff08\u201ctree-shaken\u201d\uff09\u3002\u8fd9\u4e9b\u53ea\u6709\u5728\u00a0<code>import<\/code>\/<code>export<\/code>\u00a0\u7ed3\u6784\u7b80\u5355\u4e14\u56fa\u5b9a\u7684\u60c5\u51b5\u4e0b\u624d\u80fd\u591f\u5b9e\u73b0\u3002<br \/>\n\u4f46\u662f\uff0c\u6211\u4eec\u5982\u4f55\u624d\u80fd\u52a8\u6001\u5730\u6309\u9700\u5bfc\u5165\u6a21\u5757\u5462\uff1f<\/p>\n<h2>import() \u8868\u8fbe\u5f0f<\/h2>\n<p><code>import(module)<\/code>\u00a0\u8868\u8fbe\u5f0f\u52a0\u8f7d\u6a21\u5757\u5e76\u8fd4\u56de\u4e00\u4e2a promise\uff0c\u8be5 promise resolve \u4e3a\u4e00\u4e2a\u5305\u542b\u5176\u6240\u6709\u5bfc\u51fa\u7684\u6a21\u5757\u5bf9\u8c61\u3002\u6211\u4eec\u53ef\u4ee5\u5728\u4ee3\u7801\u4e2d\u7684\u4efb\u610f\u4f4d\u7f6e\u8c03\u7528\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u3002<br \/>\n\u6211\u4eec\u53ef\u4ee5\u5728\u4ee3\u7801\u4e2d\u7684\u4efb\u610f\u4f4d\u7f6e\u52a8\u6001\u5730\u4f7f\u7528\u5b83\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code class=\"language-js\">let modulePath = prompt(&quot;Which module to load?&quot;);\n\nimport(modulePath)\n  .then(obj =&gt; &lt;module object&gt;)\n  .catch(err =&gt; &lt;loading error, e.g. if no such module&gt;)\n<\/code><\/pre>\n<p>\u6216\u8005\uff0c\u5982\u679c\u5728\u5f02\u6b65\u51fd\u6570\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u00a0<code>let module = await import(modulePath)<\/code>\u3002<br \/>\n\u4f8b\u5982\uff0c\u5982\u679c\u6211\u4eec\u6709\u4ee5\u4e0b\u6a21\u5757\u00a0<code>say.js<\/code>\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 say.js\nexport function hi() {\n  alert(`Hello`);\n}\n\nexport function bye() {\n  alert(`Bye`);\n}\n<\/code><\/pre>\n<p>\u2026\u2026\u90a3\u4e48\uff0c\u53ef\u4ee5\u50cf\u4e0b\u9762\u8fd9\u6837\u8fdb\u884c\u52a8\u6001\u5bfc\u5165\uff1a<\/p>\n<pre><code class=\"language-js\">let {hi, bye} = await import('.\/say.js');\n\nhi();\nbye();\n<\/code><\/pre>\n<p>\u6216\u8005\uff0c\u5982\u679c\u00a0<code>say.js<\/code>\u00a0\u6709\u9ed8\u8ba4\u7684\u5bfc\u51fa\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 say.js\nexport default function() {\n  alert(&quot;Module loaded (export default)!&quot;);\n}\n<\/code><\/pre>\n<p>\u2026\u2026\u90a3\u4e48\uff0c\u4e3a\u4e86\u8bbf\u95ee\u5b83\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u6a21\u5757\u5bf9\u8c61\u7684\u00a0<code>default<\/code>\u00a0\u5c5e\u6027\uff1a<\/p>\n<pre><code class=\"language-js\">let obj = await import('.\/say.js');\nlet say = obj.default;\n\/\/ or, in one line: let {default: say} = await import('.\/say.js');\n\nsay();\n<\/code><\/pre>\n<p>\u5b8c\u6574\u793a\u4f8b\uff1a<\/p>\n<pre><code class=\"language-js\">\/\/ \ud83d\udcc1 say.js\nexport function hi() {\n  alert(`Hello`);\n}\n\nexport function bye() {\n  alert(`Bye`);\n}\n\nexport default function() {\n  alert(&quot;Module loaded (export default)!&quot;);\n}\n<\/code><\/pre>\n<pre><code class=\"language-html\">\/\/ \ud83d\udcc1 index.html\n&lt;!doctype html&gt;\n&lt;script&gt;\n  async function load() {\n    let say = await import('.\/say.js');\n    say.hi(); \/\/ Hello!\n    say.bye(); \/\/ Bye!\n    say.default(); \/\/ Module loaded (export default)!\n  }\n&lt;\/script&gt;\n&lt;button onclick=&quot;load()&quot;&gt;Click me&lt;\/button&gt;\n<\/code><\/pre>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u52a8\u6001\u5bfc\u5165\u5728\u5e38\u89c4\u811a\u672c\u4e2d\u5de5\u4f5c\u65f6\uff0c\u5b83\u4eec\u4e0d\u9700\u8981\u00a0<code>script type=&quot;module&quot;<\/code>.<\/p>\n<\/blockquote>\n<blockquote>\n<p>\u8bf7\u6ce8\u610f\uff1a<br \/>\n\u5c3d\u7ba1\u00a0<code>import()<\/code>\u00a0\u770b\u8d77\u6765\u50cf\u4e00\u4e2a\u51fd\u6570\u8c03\u7528\uff0c\u4f46\u5b83\u53ea\u662f\u4e00\u79cd\u7279\u6b8a\u8bed\u6cd5\uff0c\u53ea\u662f\u6070\u597d\u4f7f\u7528\u4e86\u62ec\u53f7\uff08\u7c7b\u4f3c\u4e8e\u00a0<code>super()<\/code>\uff09\u3002<br \/>\n\u56e0\u6b64\uff0c\u6211\u4eec\u4e0d\u80fd\u5c06\u00a0<code>import<\/code>\u00a0\u590d\u5236\u5230\u4e00\u4e2a\u53d8\u91cf\u4e2d\uff0c\u6216\u8005\u5bf9\u5176\u4f7f\u7528\u00a0<code>call\/apply<\/code>\u3002\u56e0\u4e3a\u5b83\u4e0d\u662f\u4e00\u4e2a\u51fd\u6570\u3002<\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>\u6a21\u5757 Module \u7b80\u4ecb \u968f\u7740\u6211\u4eec\u7684\u5e94\u7528\u8d8a\u6765\u8d8a\u5927\uff0c\u6211\u4eec\u60f3\u8981\u5c06\u5176\u62c6\u5206\u6210\u591a\u4e2a\u6587\u4ef6\uff0c\u5373\u6240\u8c13\u7684\u201c\u6a21\u5757\uff08module\uff09\u201d [&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-675","post","type-post","status-publish","format-standard","hentry","category-front-end"],"_links":{"self":[{"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts\/675","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=675"}],"version-history":[{"count":1,"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts\/675\/revisions"}],"predecessor-version":[{"id":676,"href":"https:\/\/levin.ink\/index.php?rest_route=\/wp\/v2\/posts\/675\/revisions\/676"}],"wp:attachment":[{"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=675"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=675"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/levin.ink\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=675"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}