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<!doctype html><html lang="en-US" prefix="og: https://ogp.me/ns#"><head><meta charSet="utf-8"/><meta name="viewport" content="width=device-width,initial-scale=1"/><link rel="icon" href="https://developer.mozilla.org/favicon-48x48.bc390275e955dacb2e65.png"/><link rel="apple-touch-icon" href="https://developer.mozilla.org/apple-touch-icon.528534bba673c38049c2.png"/><meta name="theme-color" content="#ffffff"/><link rel="manifest" href="https://developer.mozilla.org/manifest.f42880861b394dd4dc9b.json"/><link rel="search" type="application/opensearchdescription+xml" href="/opensearch.xml" title="MDN Web Docs"/><title>asm.js 的异步脚本 - 游戏开发 | MDN</title><link rel="alternate" title="Async scripts for asm.js" href="https://developer.mozilla.org/en-US/docs/Games/Techniques/Async_scripts" hrefLang="en"/><link rel="alternate" title="Async-Skripte für asm.js" href="https://developer.mozilla.org/de/docs/Games/Techniques/Async_scripts" hrefLang="de"/><link rel="alternate" title="Scripts asynchrones pour asm.js" href="https://developer.mozilla.org/fr/docs/Games/Techniques/Async_scripts" hrefLang="fr"/><link rel="alternate" title="asm.js の非同期スクリプト" href="https://developer.mozilla.org/ja/docs/Games/Techniques/Async_scripts" hrefLang="ja"/><link rel="alternate" title="Асинхронные скрипты для asm.js" href="https://developer.mozilla.org/ru/docs/Games/Techniques/Async_scripts" hrefLang="ru"/><link rel="alternate" title="asm.js 的异步脚本" href="https://developer.mozilla.org/zh-CN/docs/Games/Techniques/Async_scripts" hrefLang="zh"/><link rel="preload" as="font" type="font/woff2" href="/static/media/Inter.var.c2fe3cb2b7c746f7966a.woff2" crossorigin=""/><link rel="alternate" type="application/rss+xml" title="MDN Blog RSS Feed" href="https://developer.mozilla.org/en-US/blog/rss.xml" hrefLang="en"/><meta name="description" content="每个中型或大型游戏都应编译asm.js代码作为异步脚本的一部分，以便浏览器能够最大限度地灵活地优化编译过程。在 Gecko 中，异步编译允许 JavaScript 引擎在游戏加载时缓存主线程的 asm.js，并缓存生成的机器代码，这样游戏就不需要在随后的加载中编译（从 Firefox 28 开始）。要查看差异，请切换javascript.options.parallel_parsing in about:config."/><meta property="og:url" content="https://developer.mozilla.org/zh-CN/docs/Games/Techniques/Async_scripts"/><meta property="og:title" content="asm.js 的异步脚本 - 游戏开发 | MDN"/><meta property="og:type" content="website"/><meta property="og:locale" content="zh_CN"/><meta property="og:description" content="每个中型或大型游戏都应编译asm.js代码作为异步脚本的一部分，以便浏览器能够最大限度地灵活地优化编译过程。在 Gecko 中，异步编译允许 JavaScript 引擎在游戏加载时缓存主线程的 asm.js，并缓存生成的机器代码，这样游戏就不需要在随后的加载中编译（从 Firefox 28 开始）。要查看差异，请切换javascript.options.parallel_parsing in about:config."/><meta property="og:image" content="https://developer.mozilla.org/mdn-social-share.d893525a4fb5fb1f67a2.png"/><meta property="og:image:type" content="image/png"/><meta property="og:image:height" content="1080"/><meta property="og:image:width" content="1920"/><meta property="og:image:alt" content="The MDN Web Docs logo, featuring a blue accent color, displayed on a solid black background."/><meta 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icon-cancel "></span><span class="visually-hidden">Clear filter input</span></span></button></div></section></header><div class="sidebar-inner-nav"><div class="in-nav-toc"><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">在本文中</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#异步执行">异步执行</a></li><li class="document-toc-item "><a class="document-toc-link" href="#什么时候用_async_或者不用？">什么时候用 async 或者不用？</a></li></ul></section></div></div><div class="sidebar-body"><ol><li class="toggle"><details><summary>简介</summary><ol><li><a href="/zh-CN/docs/Games/Introduction">简介</a></li><li><a href="/zh-CN/docs/Games/Anatomy">剖析</a></li></ol></details></li><li class="toggle"><details><summary>游戏开发用到的 API</summary><ol><li><a href="/zh-CN/docs/Web/API/Canvas_API">Canvas</a></li><li><a href="/zh-CN/docs/Web/CSS">CSS</a></li><li><a href="/zh-CN/docs/Web/API/Fullscreen_API">全屏</a></li><li><a href="/zh-CN/docs/Web/API/Gamepad_API">游戏控制器</a></li><li><a href="/zh-CN/docs/Web/API/IndexedDB_API">IndexedDB</a></li><li><a href="/zh-CN/docs/Web/JavaScript">JavaScript</a></li><li><a href="/zh-CN/docs/Web/API/Pointer_Lock_API">指针锁定</a></li><li><a href="/zh-CN/docs/Web/SVG">SVG</a></li><li><a href="/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/TypedArray">类型数组</a></li><li><a href="/zh-CN/docs/Web/API/Web_Audio_API">Web 音频</a></li><li><a href="/zh-CN/docs/Web/API/WebGL_API">WebGL</a></li><li><a href="/zh-CN/docs/Web/API/WebRTC_API">WebRTC</a></li><li><a href="/zh-CN/docs/Web/API/WebSockets_API">WebSocket</a></li><li><a href="/zh-CN/docs/Web/API/WebVR_API">WebVR</a><abbr class="icon icon-nonstandard" title="非标准。请在使用前检查跨浏览器支持。"> <span class="visually-hidden">非标准</span> </abbr><abbr class="icon icon-deprecated" title="已弃用。请不要在新的网站中使用。"> <span class="visually-hidden">已弃用</span> </abbr></li><li><a href="/zh-CN/docs/Web/API/Web_Workers_API">Web Worker</a></li><li><a href="/zh-CN/docs/Web/API/XMLHttpRequest">XMLHttpRequest</a></li></ol></details></li><li class="toggle"><details open=""><summary>技术</summary><ol><li><em><a href="/zh-CN/docs/Games/Techniques/Async_scripts" aria-current="page">使用 asm.js 中的异步脚本</a></em></li><li><a href="/zh-CN/docs/Web/Performance/Guides/Optimizing_startup_performance">优化启动性能</a></li><li><a href="/en-US/docs/Games/Techniques/WebRTC_data_channels" class="only-in-en-us">使用 WebRTC 点对点数据通道</a></li><li><a href="/en-US/docs/Games/Techniques/Audio_for_Web_Games" class="only-in-en-us">Web 游戏的音频</a></li><li><a href="/zh-CN/docs/Games/Techniques/2D_collision_detection">2D 碰撞检测</a></li><li><a href="/en-US/docs/Games/Techniques/Tilemaps" class="only-in-en-us">平铺和平铺贴图概述</a></li></ol></details></li><li class="toggle"><details><summary>Web 中的 3D 游戏</summary><ol><li><a href="/zh-CN/docs/Games/Techniques/3D_on_the_web">概述</a></li><li><a href="/zh-CN/docs/Games/Techniques/3D_on_the_web/Basic_theory">基本的 3D 理论</a></li><li><a href="/en-US/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_A-Frame" class="only-in-en-us">使用 A-Frame 构建基础演示</a></li><li><a href="/en-US/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_Babylon.js" class="only-in-en-us">使用 Babylon.js 构建基础演示</a></li><li><a href="/en-US/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_PlayCanvas" class="only-in-en-us">使用 PlayCanvas 构建基础演示</a></li><li><a href="/zh-CN/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_Three.js">使用 Three.js 构建基础演示</a></li><li><a href="/en-US/docs/Games/Techniques/3D_on_the_web/WebXR" class="only-in-en-us">WebXR</a></li><li><a href="/zh-CN/docs/Games/Techniques/3D_collision_detection">3D 碰撞检测</a></li><li><a href="/en-US/docs/Games/Techniques/3D_collision_detection/Bounding_volume_collision_detection_with_THREE.js" class="only-in-en-us">使用 THREE.js 进行边界体积碰撞检测</a></li></ol></details></li><li class="toggle"><details><summary>实现游戏控制机制</summary><ol><li><a href="/zh-CN/docs/Games/Techniques/Control_mechanisms">控制机制</a></li><li><a href="/zh-CN/docs/Games/Techniques/Control_mechanisms/Mobile_touch">移动端触摸</a></li><li><a href="/en-US/docs/Games/Techniques/Control_mechanisms/Desktop_with_mouse_and_keyboard" class="only-in-en-us">通过鼠标和键盘控制的桌面端</a></li><li><a href="/en-US/docs/Games/Techniques/Control_mechanisms/Desktop_with_gamepad" class="only-in-en-us">通过游戏手柄控制的桌面端</a></li><li><a href="/en-US/docs/Games/Techniques/Control_mechanisms/Other" class="only-in-en-us">其他</a></li></ol></details></li><li class="toggle"><details><summary>教程</summary><ol><li><a href="/zh-CN/docs/Games/Tutorials/2D_Breakout_game_pure_JavaScript">使用纯 JavaScript 实现 2D 打砖块游戏</a></li><li><a href="/zh-CN/docs/Games/Tutorials/2D_breakout_game_Phaser">使用 Phaser 实现 2D 打砖块游戏</a></li><li><a href="/en-US/docs/Games/Tutorials/HTML5_Gamedev_Phaser_Device_Orientation" class="only-in-en-us">具有设备方向检测功能的 2D 迷宫游戏</a></li><li><a href="https://mozdevs.github.io/html5-games-workshop/en/guides/platformer/start-here/" class="external" target="_blank">使用 Phaser 实现 2D 平板游戏</a></li></ol></details></li><li class="toggle"><details><summary>发布游戏</summary><ol><li><a href="/zh-CN/docs/Games/Publishing_games">概述</a></li><li><a href="/zh-CN/docs/Games/Publishing_games/Game_distribution">游戏分发</a></li><li><a href="/zh-CN/docs/Games/Publishing_games/Game_promotion">游戏推广</a></li><li><a href="/zh-CN/docs/Games/Publishing_games/Game_monetization">游戏盈利</a></li></ol></details></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">在本文中</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#异步执行">异步执行</a></li><li class="document-toc-item "><a class="document-toc-link" href="#什么时候用_async_或者不用？">什么时候用 async 或者不用？</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="zh-CN"><header><h1>asm.js 的异步脚本</h1></header><div class="section-content"><p>每个中型或大型游戏都应编译<a href="/en-US/docs/Games/Tools/asm.js" class="only-in-en-us">asm.js</a>代码作为异步脚本的一部分，以便浏览器能够最大限度地灵活地优化编译过程。在 Gecko 中，异步编译允许 JavaScript 引擎在游戏加载时缓存主线程的 asm.js，并缓存生成的机器代码，这样游戏就不需要在随后的加载中编译（从 Firefox 28 开始）。要查看差异，请切换<code>javascript.options.parallel_parsing</code> in <code>about:config</code>.</p></div><section aria-labelledby="异步执行"><h2 id="异步执行"><a href="#异步执行">异步执行</a></h2><div class="section-content"><p>获取异步编译非常简单：编写 JavaScript 时，只需使用 <code>async</code> 属性即可：</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code><script async src="file.js"></script> </code></pre></div> <p>或者，通过脚本来做同样的事情：</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>const script = document.createElement("script"); script.src = "file.js"; document.body.appendChild(script); </code></pre></div> <p>（从脚本中创建的脚本默认为异步。）默认的 HTML shell Emscripten 生成后者。</p></div></section><section aria-labelledby="什么时候用_async_或者不用？"><h2 id="什么时候用_async_或者不用？"><a href="#什么时候用_async_或者不用？">什么时候用 async 或者不用？</a></h2><div class="section-content"><p>两种常见的情况下是脚本是<strong>非</strong>异步的（由<a href="https://www.w3.org/TR/html5/scripting-1.html" class="external" target="_blank">HTML 规范</a>定义）</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code><script async>code();</script> </code></pre></div> <p>以及</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>const script = document.createElement("script"); script.textContent = "code()"; document.body.appendChild(script); </code></pre></div> <p>两者都被视为“内联”脚本，阻塞其余所有任务，进行编译，编译完成后立即执行。</p> <p>如果你的代码是一个 JS 字符串呢？你应该使用带有对象 URL（object URL）的 Blob 对象，而不是使用 <code>eval</code> 或 <code>innerHTML</code>，这两者都会触发同步编译：</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>const blob = new Blob([codeString]); const script = document.createElement("script"); const url = URL.createObjectURL(blob); script.onload = script.onerror = () => URL.revokeObjectURL(url); script.src = url; document.body.appendChild(script); </code></pre></div> <p>使用<code>src</code>而不是<code>innerHTML，则该</code>脚本是异步的。</p></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 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content are ©1998–2025 by individual mozilla.org contributors. Content available under <a href="/zh-CN/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/zh-CN/docs/Games/Techniques/Async_scripts","doc":{"body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>每个中型或大型游戏都应编译<a href=\"/en-US/docs/Games/Tools/asm.js\" class=\"only-in-en-us\">asm.js</a>代码作为异步脚本的一部分，以便浏览器能够最大限度地灵活地优化编译过程。在 Gecko 中，异步编译允许 JavaScript 引擎在游戏加载时缓存主线程的 asm.js，并缓存生成的机器代码，这样游戏就不需要在随后的加载中编译（从 Firefox 28 开始）。要查看差异，请切换<code>javascript.options.parallel_parsing</code> in <code>about:config</code>.</p>"}},{"type":"prose","value":{"id":"异步执行","title":"异步执行","isH3":false,"content":"<p>获取异步编译非常简单：编写 JavaScript 时，只需使用 <code>async</code> 属性即可：</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code><script async src=\"file.js\"></script>\n</code></pre></div>\n<p>或者，通过脚本来做同样的事情：</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>const script = document.createElement(\"script\");\nscript.src = \"file.js\";\ndocument.body.appendChild(script);\n</code></pre></div>\n<p>（从脚本中创建的脚本默认为异步。）默认的 HTML shell Emscripten 生成后者。</p>"}},{"type":"prose","value":{"id":"什么时候用_async_或者不用？","title":"什么时候用 async 或者不用？","isH3":false,"content":"<p>两种常见的情况下是脚本是<strong>非</strong>异步的（由<a href=\"https://www.w3.org/TR/html5/scripting-1.html\" class=\"external\" target=\"_blank\">HTML 规范</a>定义）</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code><script async>code();</script>\n</code></pre></div>\n<p>以及</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>const script = document.createElement(\"script\");\nscript.textContent = \"code()\";\ndocument.body.appendChild(script);\n</code></pre></div>\n<p>两者都被视为“内联”脚本，阻塞其余所有任务，进行编译，编译完成后立即执行。</p>\n<p>如果你的代码是一个 JS 字符串呢？你应该使用带有对象 URL（object URL）的 Blob 对象，而不是使用 <code>eval</code> 或 <code>innerHTML</code>，这两者都会触发同步编译：</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>const blob = new Blob([codeString]);\nconst script = document.createElement(\"script\");\nconst url = URL.createObjectURL(blob);\nscript.onload = script.onerror = () => URL.revokeObjectURL(url);\nscript.src = url;\ndocument.body.appendChild(script);\n</code></pre></div>\n<p>使用<code>src</code>而不是<code>innerHTML，则该</code>脚本是异步的。</p>"}}],"isActive":true,"isMarkdown":true,"isTranslated":true,"locale":"zh-CN","mdn_url":"/zh-CN/docs/Games/Techniques/Async_scripts","modified":"2023-07-16T09:38:46.000Z","native":"中文 (简体)","noIndexing":false,"other_translations":[{"locale":"en-US","title":"Async scripts for asm.js","native":"English (US)"},{"locale":"de","title":"Async-Skripte für asm.js","native":"Deutsch"},{"locale":"fr","title":"Scripts asynchrones pour asm.js","native":"Français"},{"locale":"ja","title":"asm.js の非同期スクリプト","native":"日本語"},{"locale":"ru","title":"Асинхронные скрипты для asm.js","native":"Русский"}],"pageTitle":"asm.js 的异步脚本 - 游戏开发 | MDN","parents":[{"uri":"/zh-CN/docs/Games","title":"游戏开发"},{"uri":"/zh-CN/docs/Games/Techniques","title":"游戏开发技术"},{"uri":"/zh-CN/docs/Games/Techniques/Async_scripts","title":"asm.js 的异步脚本"}],"popularity":null,"short_title":"asm.js 的异步脚本","sidebarHTML":"<ol><li class=\"toggle\"><details><summary>简介</summary><ol><li><a href=\"/zh-CN/docs/Games/Introduction\">简介</a></li><li><a href=\"/zh-CN/docs/Games/Anatomy\">剖析</a></li></ol></details></li><li class=\"toggle\"><details><summary>游戏开发用到的 API</summary><ol><li><a href=\"/zh-CN/docs/Web/API/Canvas_API\">Canvas</a></li><li><a href=\"/zh-CN/docs/Web/CSS\">CSS</a></li><li><a href=\"/zh-CN/docs/Web/API/Fullscreen_API\">全屏</a></li><li><a href=\"/zh-CN/docs/Web/API/Gamepad_API\">游戏控制器</a></li><li><a href=\"/zh-CN/docs/Web/API/IndexedDB_API\">IndexedDB</a></li><li><a href=\"/zh-CN/docs/Web/JavaScript\">JavaScript</a></li><li><a href=\"/zh-CN/docs/Web/API/Pointer_Lock_API\">指针锁定</a></li><li><a href=\"/zh-CN/docs/Web/SVG\">SVG</a></li><li><a href=\"/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/TypedArray\">类型数组</a></li><li><a href=\"/zh-CN/docs/Web/API/Web_Audio_API\">Web 音频</a></li><li><a href=\"/zh-CN/docs/Web/API/WebGL_API\">WebGL</a></li><li><a href=\"/zh-CN/docs/Web/API/WebRTC_API\">WebRTC</a></li><li><a href=\"/zh-CN/docs/Web/API/WebSockets_API\">WebSocket</a></li><li><a href=\"/zh-CN/docs/Web/API/WebVR_API\">WebVR</a><abbr class=\"icon icon-nonstandard\" title=\"非标准。请在使用前检查跨浏览器支持。\">\n<span class=\"visually-hidden\">非标准</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"已弃用。请不要在新的网站中使用。\">\n<span class=\"visually-hidden\">已弃用</span>\n</abbr></li><li><a href=\"/zh-CN/docs/Web/API/Web_Workers_API\">Web Worker</a></li><li><a href=\"/zh-CN/docs/Web/API/XMLHttpRequest\">XMLHttpRequest</a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>技术</summary><ol><li><em><a href=\"/zh-CN/docs/Games/Techniques/Async_scripts\" aria-current=\"page\">使用 asm.js 中的异步脚本</a></em></li><li><a href=\"/zh-CN/docs/Web/Performance/Guides/Optimizing_startup_performance\">优化启动性能</a></li><li><a href=\"/en-US/docs/Games/Techniques/WebRTC_data_channels\" class=\"only-in-en-us\">使用 WebRTC 点对点数据通道</a></li><li><a href=\"/en-US/docs/Games/Techniques/Audio_for_Web_Games\" class=\"only-in-en-us\">Web 游戏的音频</a></li><li><a href=\"/zh-CN/docs/Games/Techniques/2D_collision_detection\">2D 碰撞检测</a></li><li><a href=\"/en-US/docs/Games/Techniques/Tilemaps\" class=\"only-in-en-us\">平铺和平铺贴图概述</a></li></ol></details></li><li class=\"toggle\"><details><summary>Web 中的 3D 游戏</summary><ol><li><a href=\"/zh-CN/docs/Games/Techniques/3D_on_the_web\">概述</a></li><li><a href=\"/zh-CN/docs/Games/Techniques/3D_on_the_web/Basic_theory\">基本的 3D 理论</a></li><li><a href=\"/en-US/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_A-Frame\" class=\"only-in-en-us\">使用 A-Frame 构建基础演示</a></li><li><a href=\"/en-US/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_Babylon.js\" class=\"only-in-en-us\">使用 Babylon.js 构建基础演示</a></li><li><a href=\"/en-US/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_PlayCanvas\" class=\"only-in-en-us\">使用 PlayCanvas 构建基础演示</a></li><li><a href=\"/zh-CN/docs/Games/Techniques/3D_on_the_web/Building_up_a_basic_demo_with_Three.js\">使用 Three.js 构建基础演示</a></li><li><a href=\"/en-US/docs/Games/Techniques/3D_on_the_web/WebXR\" class=\"only-in-en-us\">WebXR</a></li><li><a href=\"/zh-CN/docs/Games/Techniques/3D_collision_detection\">3D 碰撞检测</a></li><li><a href=\"/en-US/docs/Games/Techniques/3D_collision_detection/Bounding_volume_collision_detection_with_THREE.js\" class=\"only-in-en-us\">使用 THREE.js 进行边界体积碰撞检测</a></li></ol></details></li><li class=\"toggle\"><details><summary>实现游戏控制机制</summary><ol><li><a href=\"/zh-CN/docs/Games/Techniques/Control_mechanisms\">控制机制</a></li><li><a href=\"/zh-CN/docs/Games/Techniques/Control_mechanisms/Mobile_touch\">移动端触摸</a></li><li><a href=\"/en-US/docs/Games/Techniques/Control_mechanisms/Desktop_with_mouse_and_keyboard\" class=\"only-in-en-us\">通过鼠标和键盘控制的桌面端</a></li><li><a href=\"/en-US/docs/Games/Techniques/Control_mechanisms/Desktop_with_gamepad\" class=\"only-in-en-us\">通过游戏手柄控制的桌面端</a></li><li><a href=\"/en-US/docs/Games/Techniques/Control_mechanisms/Other\" class=\"only-in-en-us\">其他</a></li></ol></details></li><li class=\"toggle\"><details><summary>教程</summary><ol><li><a href=\"/zh-CN/docs/Games/Tutorials/2D_Breakout_game_pure_JavaScript\">使用纯 JavaScript 实现 2D 打砖块游戏</a></li><li><a href=\"/zh-CN/docs/Games/Tutorials/2D_breakout_game_Phaser\">使用 Phaser 实现 2D 打砖块游戏</a></li><li><a href=\"/en-US/docs/Games/Tutorials/HTML5_Gamedev_Phaser_Device_Orientation\" class=\"only-in-en-us\">具有设备方向检测功能的 2D 迷宫游戏</a></li><li><a href=\"https://mozdevs.github.io/html5-games-workshop/en/guides/platformer/start-here/\" class=\"external\" target=\"_blank\">使用 Phaser 实现 2D 平板游戏</a></li></ol></details></li><li class=\"toggle\"><details><summary>发布游戏</summary><ol><li><a href=\"/zh-CN/docs/Games/Publishing_games\">概述</a></li><li><a href=\"/zh-CN/docs/Games/Publishing_games/Game_distribution\">游戏分发</a></li><li><a href=\"/zh-CN/docs/Games/Publishing_games/Game_promotion\">游戏推广</a></li><li><a href=\"/zh-CN/docs/Games/Publishing_games/Game_monetization\">游戏盈利</a></li></ol></details></li></ol>","source":{"folder":"zh-cn/games/techniques/async_scripts","github_url":"https://github.com/mdn/translated-content/blob/main/files/zh-cn/games/techniques/async_scripts/index.md","last_commit_url":"https://github.com/mdn/translated-content/commit/1fc42dd7ed606d3adb0c8e90d22cca445e65b720","filename":"index.md"},"summary":"每个中型或大型游戏都应编译asm.js代码作为异步脚本的一部分，以便浏览器能够最大限度地灵活地优化编译过程。在 Gecko 中，异步编译允许 JavaScript 引擎在游戏加载时缓存主线程的 asm.js，并缓存生成的机器代码，这样游戏就不需要在随后的加载中编译（从 Firefox 28 开始）。要查看差异，请切换javascript.options.parallel_parsing in about:config.","title":"asm.js 的异步脚本","toc":[{"text":"异步执行","id":"异步执行"},{"text":"什么时候用 async 或者不用？","id":"什么时候用_async_或者不用？"}],"pageType":"guide"}}</script></body></html>