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JavaScript</summary><ol><li><em><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous" aria-current="page">异步 JavaScript</a></em></li><li><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing">异步 JavaScript 简介</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Promises">如何使用 Promise</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Implementing_a_promise-based_API">如何实现基于 Promise 的 API</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing_workers">workers 简介</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Sequencing_animations">序列动画</a></li></ol></details></li><li><details><summary>客户端 Web API</summary><ol><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs">客户端 Web API</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Introduction">Web API 简介</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Manipulating_documents">操作文档</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Fetching_data">从服务器获取数据</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Third_party_APIs">第三方 API</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Drawing_graphics">绘图</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Video_and_audio_APIs">视频和音频 API</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Client-side_storage">客户端存储</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/Forms">Web 表单——与用户数据打交道</a></li><li><details><summary>Web 表单核心</summary><ol><li><a href="/zh-CN/docs/Learn/Forms">Web 表单构建块</a></li><li><a href="/zh-CN/docs/Learn/Forms/Your_first_form">创建我的第一个表单</a></li><li><a href="/zh-CN/docs/Learn/Forms/How_to_structure_a_web_form">如何构建 HTML 表单</a></li><li><a href="/zh-CN/docs/Learn/Forms/Basic_native_form_controls">原生表单部件</a></li><li><a href="/zh-CN/docs/Learn/Forms/HTML5_input_types">HTML5 的输入（input）类型</a></li><li><a href="/zh-CN/docs/Learn/Forms/Other_form_controls">其他表单控件</a></li><li><a href="/zh-CN/docs/Learn/Forms/Styling_web_forms">样式化 Web 表单</a></li><li><a href="/zh-CN/docs/Learn/Forms/Advanced_form_styling">表单样式化进阶</a></li><li><a href="/zh-CN/docs/Learn/Forms/UI_pseudo-classes">UI 伪类</a></li><li><a href="/zh-CN/docs/Learn/Forms/Form_validation">表单数据校验</a></li><li><a href="/zh-CN/docs/Learn/Forms/Sending_and_retrieving_form_data">发送表单数据</a></li></ol></details></li><li><details><summary>Web 表单进阶</summary><ol><li><a href="/zh-CN/docs/Learn/Forms/How_to_build_custom_form_controls">如何构建自定义表单控件</a></li><li><a href="/zh-CN/docs/Learn/Forms/Sending_forms_through_JavaScript">使用 JavaScript 发送表单</a></li><li><a href="/zh-CN/docs/Learn/Forms/Property_compatibility_table_for_form_controls">表单控件兼容性列表</a></li><li><a href="/zh-CN/docs/Learn/Forms/HTML_forms_in_legacy_browsers">旧式浏览器中的 HTML 表单</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/Accessibility">无障碍——使每个人都能使用 Web</a></li><li><details><summary>无障碍指南</summary><ol><li><a href="/zh-CN/docs/Learn/Accessibility">无障碍</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/What_is_accessibility">什么是无障碍？</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/HTML">HTML：无障碍的良好基础</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/CSS_and_JavaScript">CSS 和 JavaScript 无障碍最佳实践</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/WAI-ARIA_basics">WAI-ARIA 基础</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/Multimedia">多媒体无障碍</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/Mobile">移动端无障碍</a></li><li><a href="/zh-CN/docs/Learn/Accessibility/Accessibility_troubleshooting">测验：无障碍疑难解答</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/Performance">性能——使网站快速响应</a></li><li><details><summary>性能指南</summary><ol><li><a href="/zh-CN/docs/Learn/Performance">Web 性能</a></li><li><a href="/zh-CN/docs/Learn/Performance/why_web_performance">Web 性能的重要性</a></li><li><a href="/zh-CN/docs/Learn/Performance/What_is_web_performance">什么是 web 性能？</a></li><li><a href="/zh-CN/docs/Learn/Performance/Perceived_performance">感知性能</a></li><li><a href="/zh-CN/docs/Learn/Performance/Measuring_performance">测量性能</a></li><li><a href="/zh-CN/docs/Learn/Performance/Multimedia">多媒体：图片</a></li><li><a href="/zh-CN/docs/Learn/Performance/video">多媒体：视频</a></li><li><a href="/zh-CN/docs/Learn/Performance/JavaScript">JavaScript 性能优化</a></li><li><a href="/zh-CN/docs/Learn/Performance/HTML">HTML 性能优化</a></li><li><a href="/zh-CN/docs/Learn/Performance/CSS">CSS 性能优化</a></li><li><a href="/zh-CN/docs/Learn/Performance/business_case_for_performance">web 性能的商业案例</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/MathML">MathML——使用 MathML 语言撰写数学表达式</a></li><li><details><summary>MathML 第一步</summary><ol><li><a href="/zh-CN/docs/Learn/MathML/First_steps">MathML 入门概述</a></li><li><a href="/zh-CN/docs/Learn/MathML/First_steps/Getting_started">MathML 使用入门</a></li><li><a href="/zh-CN/docs/Learn/MathML/First_steps/Text_containers">MathML 文本容器</a></li><li><a href="/zh-CN/docs/Learn/MathML/First_steps/Fractions_and_roots">MathML 分数和根号</a></li><li><a href="/zh-CN/docs/Learn/MathML/First_steps/Scripts">MathML 附加符号</a></li><li><a href="/zh-CN/docs/Learn/MathML/First_steps/Tables">MathML 表格</a></li><li><a href="/zh-CN/docs/Learn/MathML/First_steps/Three_famous_mathematical_formulas">三个著名的数学公式</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/../Games">游戏——开发 Web 游戏</a></li><li><details><summary>指南和基础教程</summary><ol><li><a href="/zh-CN/docs/Games/Introduction">Web 游戏开发简介</a></li><li><a href="/zh-CN/docs/Games/Techniques">游戏开发技术</a></li><li><a href="/zh-CN/docs/Games/Tutorials">教程</a></li><li><a href="/zh-CN/docs/Games/Publishing_games">发布游戏</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/Tools_and_testing">工具与测试</a></li><li><details><summary>客户端 web 开发工具</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools">理解客户端 web 开发工具</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Overview">客户端工具概述</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Command_line">命令行速成课</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Package_management">软件包管理基础</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Introducing_complete_toolchain">介绍完整的工具链</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Deployment">部署我们的应用</a></li></ol></details></li><li><details><summary>客户端框架介绍</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Introduction">客户端框架介绍</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Main_features">框架的主要特性</a></li></ol></details></li><li><details><summary>React</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_getting_started">React 入门</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_todo_list_beginning">开始我们的 React 待办清单</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_components">组件化我们的 React App</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_interactivity_events_state">React interactivity: Events and state</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_interactivity_filtering_conditional_rendering">React interactivity: Editing, filtering, conditional rendering</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_accessibility">Accessibility in React</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_resources">React resources</a></li></ol></details></li><li><details><summary>Ember</summary><ol><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_getting_started">Getting started with Ember</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_structure_componentization">Ember app structure and componentization</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_interactivity_events_state">Ember interactivity: Events, classes and state</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_conditional_footer">Ember Interactivity: Footer functionality, conditional rendering</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_routing">Routing in Ember</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_resources">Ember resources and troubleshooting</a></li></ol></details></li><li><details><summary>Vue</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_getting_started">开始使用 Vue</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_first_component">创建第一个 Vue 组件</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_rendering_lists">渲染 Vue 组件列表</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_methods_events_models">使用 Vue event、method 和 model 添加一个新的 todo 表单</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_styling">使用 CSS 为 Vue 组件添加样式</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_computed_properties">Vue 中的计算属性</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_conditional_rendering">Vue 中的条件渲染：编辑现有的待办事项</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_refs_focus_management">使用 Vue 模板引用进行焦点管理</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_resources">Vue 资源</a></li></ol></details></li><li><details><summary>Svelte</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_getting_started">Svelte 入门</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_Todo_list_beginning">开始编写我们的 Svelte 待办事项列表应用程序</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_variables_props">Svelte 中的动态行为：变量和属性</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_components">将我们的 Svelte 应用组件化</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_reactivity_lifecycle_accessibility">Svelte 进阶：响应式、生命周期以及无障碍</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_stores">使用 Svelte store</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_TypeScript">Svelte 对 TypeScript 的支持</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_deployment_next">部署以及下一步</a></li></ol></details></li><li><details><summary>Angular</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_getting_started">Angular 入门</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_todo_list_beginning">Beginning our Angular todo list app</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_styling">Styling our Angular app</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_item_component">Creating an item component</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_filtering">Filtering our to-do items</a></li><li><a class="only-in-en-us" title="此页面目前仅提供英文版本" href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_building">Building Angular applications and further resources</a></li></ol></details></li><li><details><summary>Git 和 GitHub</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/GitHub">Git 和 GitHub</a></li></ol></details></li><li><details><summary>跨浏览器测试</summary><ol><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing">跨浏览器测试</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Introduction">跨浏览器测试介绍</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Testing_strategies">测试的策略</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/HTML_and_CSS">处理常见的 HTML 和 CSS 问题</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/JavaScript">处理常见的 JavaScript 问题</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Accessibility">解决常见的无障碍问题</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Feature_detection">实现特性检测</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Automated_testing">自动化测试简介</a></li><li><a href="/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Your_own_automation_environment">搭建自己的自动化测试环境</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/Server-side">服务端网页编程</a></li><li><details><summary>第一步</summary><ol><li><a href="/zh-CN/docs/Learn/Server-side/First_steps">服务端网站编程的第一步</a></li><li><a href="/zh-CN/docs/Learn/Server-side/First_steps/Introduction">服务端编程介绍</a></li><li><a href="/zh-CN/docs/Learn/Server-side/First_steps/Client-Server_overview">客户端服务端交互概述</a></li><li><a href="/zh-CN/docs/Learn/Server-side/First_steps/Web_frameworks">服务端 web 框架</a></li><li><a href="/zh-CN/docs/Learn/Server-side/First_steps/Website_security">站点安全</a></li></ol></details></li><li><details><summary>Django Web 框架（Python）</summary><ol><li><a href="/zh-CN/docs/Learn/Server-side/Django">Django Web 框架 (python)</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Introduction">Django 介绍</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/development_environment">设置 Django 开发环境</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Tutorial_local_library_website">Django Tutorial: The Local Library website</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/skeleton_website">Django Tutorial Part 2: 创建网站的地基</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Models">Django Tutorial Part 3: 使用模型</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Admin_site">Django Tutorial Part 4: Django 管理员站点</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Home_page">Django 教程 5：主页构建</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Generic_views">Django 教程 6: 通用列表和详细信息视图</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Sessions">Django 教程 7: 会话框架</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Authentication">Django 教程 8：用户授权与许可</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Forms">Django 教程 9: 使用表单</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Testing">Django 教程 10: 测试 Django 网页应用</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/Deployment">Django 教程 11：部署 Django 到生产环境</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/web_application_security">Django Web 应用安全</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Django/django_assessment_blog">评估：DIY Django 微博客</a></li></ol></details></li><li><details><summary>Express Web 框架（Node.js/JavaScript）</summary><ol><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs">Express Web 框架（Node.js/JavaScript）</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/Introduction">Express/Node 入门</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/development_environment">设置 Node 开发环境</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/Tutorial_local_library_website">Express 教程：本地图书馆网站</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/skeleton_website">Express 教程 2：创建站点框架</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/mongoose">Express 教程 3：使用数据库 (Mongoose)</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/routes">Express 教程 4：路由和控制器</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/Displaying_data">Express 教程 5: 呈现图书馆数据</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/forms">Express 教程 6: 使用表单</a></li><li><a href="/zh-CN/docs/Learn/Server-side/Express_Nodejs/deployment">Express 教程 7: 部署到生产环境</a></li></ol></details></li><li class="section"><a href="/zh-CN/docs/Learn/Common_questions">更多资源</a></li><li><details><summary>常见问题</summary><ol><li><a href="/zh-CN/docs/Learn/Common_questions">常见问题</a></li><li><a href="/zh-CN/docs/Learn/HTML/Howto">使用 HTML 解决常见问题</a></li><li><a href="/zh-CN/docs/Learn/CSS/Howto">解决常见的 CSS 问题</a></li><li><a href="/zh-CN/docs/Learn/JavaScript/Howto">解决 JavaSctript 代码的常见问题</a></li><li><a href="/zh-CN/docs/Learn/Common_questions/Web_mechanics">Web 机制</a></li><li><a href="/zh-CN/docs/Learn/Common_questions/Tools_and_setup">工具和安装</a></li><li><a href="/zh-CN/docs/Learn/Common_questions/Design_and_accessibility">设计与无障碍</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="#预备知识">预备知识</a></li><li class="document-toc-item "><a class="document-toc-link" href="#指南">指南</a></li><li class="document-toc-item "><a class="document-toc-link" href="#测验">测验</a></li><li class="document-toc-item "><a class="document-toc-link" href="#参见">参见</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>异步 JavaScript</h1></header><div class="section-content"><p>在这个模块，我们将查看<a href="/zh-CN/docs/Glossary/Asynchronous">异步</a> <a href="/zh-CN/docs/Glossary/JavaScript">JavaScript</a>，异步为什么很重要，以及怎样使用异步来有效处理潜在的阻塞操作，比如从服务器上获取资源。</p></div><section aria-labelledby="预备知识"><h2 id="预备知识"><a href="#预备知识">预备知识</a></h2><div class="section-content"><p>异步 JavaScript 是一个相当高级的话题，建议你先完成 <a href="/zh-CN/docs/Learn/JavaScript/First_steps">JavaScript 第一步</a>和<a href="/zh-CN/docs/Learn/JavaScript/Building_blocks">创建 JavaScript 代码块</a> 两个模块的学习后再来学习。</p> <div class="notecard note"> <p><strong>备注：</strong>如果你工作在一个无权创建自己文件的电脑/平板/其他设备上，你需要在一个在线编程工具上试验（大多数）代码示例，如 <a href="https://jsbin.com/" class="external" target="_blank">JSBin</a> 或者 <a href="https://glitch.com" class="external" target="_blank">Glitch</a>.</p> </div></div></section><section aria-labelledby="指南"><h2 id="指南"><a href="#指南">指南</a></h2><div class="section-content"><dl> <dt id="异步_javascript_简介"><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing">异步 JavaScript 简介</a></dt> <dd> <p>在这篇文章中我们将介绍 <strong>同步编程</strong> 和 <strong>异步编程</strong> 是什么，为什么我们总是需要异步编程技术，异步函数过去是怎样在 JavaScript 上实现的，以及这些方式的问题有哪些。</p> </dd> <dt id="如何使用_promise"><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Promises">如何使用 Promise</a></dt> <dd> <p>我们将在这里介绍 Promise 并向你展示如何使用基于 Promise 的 API。我们也会介绍 <code>async</code> 和 <code>await</code> 关键字。</p> </dd> <dt id="应用一个基于_promise_的_api"><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Implementing_a_promise-based_API">应用一个基于 Promise 的 API</a></dt> <dd> <p>本文概述了如何实现一个我们自己的基于 Promise 的 API。</p> </dd> <dt id="worker_简介"><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing_workers">Worker 简介</a></dt> <dd> <p>Worker 使你能够在独立的线程中运行任务来保持你的主要代码的可响应性。在这篇文章中我们将把一个长时间运行的同步函数重写为使用 Worker 的示例。</p> </dd> </dl></div></section><section aria-labelledby="测验"><h2 id="测验"><a href="#测验">测验</a></h2><div class="section-content"><dl> <dt id="序列动画"><a href="/zh-CN/docs/Learn/JavaScript/Asynchronous/Sequencing_animations">序列动画</a></dt> <dd> <p>这个测验要求你使用 Promise 来播放一组特定序列的动画。</p> </dd> </dl></div></section><section aria-labelledby="参见"><h2 id="参见"><a href="#参见">参见</a></h2><div class="section-content"><ul> <li>由 Marijn Haverbeke 编写的电子书籍 <a href="https://eloquentjavascript.net/" class="external" target="_blank">Eloquent JavaScript</a> 中的 <a href="https://eloquentjavascript.net/11_async.html" class="external" target="_blank">异步编程</a>。</li> </ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg 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href=\"/zh-CN/docs/Learn/Getting_started_with_the_web/HTML_basics\">HTML 基础</a></li><li><a href=\"/zh-CN/docs/Learn/Getting_started_with_the_web/CSS_basics\">CSS 基础</a></li><li><a href=\"/zh-CN/docs/Learn/Getting_started_with_the_web/JavaScript_basics\">JavaScript 基础</a></li><li><a href=\"/zh-CN/docs/Learn/Getting_started_with_the_web/Publishing_your_website\">发布你的网站</a></li><li><a href=\"/zh-CN/docs/Learn/Getting_started_with_the_web/How_the_Web_works\">万维网是如何工作的</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/HTML\">HTML——构建 Web</a></li><li><details><summary>HTML 介绍</summary><ol><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML\">HTML 简介</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Getting_started\">开始学习 HTML</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/The_head_metadata_in_HTML\">“头”里有什么——HTML 元信息</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/HTML_text_fundamentals\">HTML 文本处理基础</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Creating_hyperlinks\">创建超链接</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Advanced_text_formatting\">文本格式进阶</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Document_and_website_structure\">文档与网站架构</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Debugging_HTML\">HTML 调试</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Marking_up_a_letter\">标记信件</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Introduction_to_HTML/Structuring_a_page_of_content\">构建网页内容</a></li></ol></details></li><li><details><summary>多媒体与嵌入</summary><ol><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding\">多媒体与嵌入</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding/Images_in_HTML\">HTML 中的图片</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding/Video_and_audio_content\">视频和音频内容</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding/Other_embedding_technologies\">从 object 到 iframe——其他嵌入技术</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding/Adding_vector_graphics_to_the_Web\">向 web 中添加矢量图形</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding/Responsive_images\">响应式图片</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Multimedia_and_embedding/Mozilla_splash_page\">Mozilla 欢迎页面</a></li></ol></details></li><li><details><summary>HTML 表格</summary><ol><li><a href=\"/zh-CN/docs/Learn/HTML/Tables\">HTML 表格</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Tables/Basics\">HTML 表格基础</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Tables/Advanced\">HTML 表格进阶特性和无障碍</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Tables/Structuring_planet_data\">作业：构建行星数据</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/CSS\">CSS——设计 Web</a></li><li><details><summary>CSS 第一步</summary><ol><li><a href=\"/zh-CN/docs/Learn/CSS/First_steps\">CSS 入门概述</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/First_steps/What_is_CSS\">什么是 CSS?</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/First_steps/Getting_started\">让我们开始 CSS 的学习之旅</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/First_steps/How_CSS_is_structured\">CSS 的组成</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/First_steps/How_CSS_works\">CSS 如何运行</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/First_steps/Styling_a_biography_page\">运用你的新知识</a></li></ol></details></li><li><details><summary>CSS 基础</summary><ol><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks\">CSS 构建</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Selectors\">CSS 选择器</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Selectors/Type_Class_and_ID_Selectors\">类型、类和 ID 选择器</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Selectors/Attribute_selectors\">属性选择器</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Selectors/Pseudo-classes_and_pseudo-elements\">伪类和伪元素</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Selectors/Combinators\">关系选择器</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Cascade_and_inheritance\">层叠、优先级与继承</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Cascade_layers\">层叠层</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/The_box_model\">盒模型</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Backgrounds_and_borders\">背景与边框</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Handling_different_text_directions\">处理不同方向的文本</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Overflowing_content\">溢出的内容</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Values_and_units\">CSS 值和单位</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Sizing_items_in_CSS\">在 CSS 中调整大小</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Images_media_form_elements\">图像、媒体和表单元素</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Styling_tables\">样式化表格</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Advanced_styling_effects\">高级区块效果</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Debugging_CSS\">调试 CSS</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Organizing\">组织 CSS</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Fundamental_CSS_comprehension\">基本的 CSS 理解</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/Creating_fancy_letterheaded_paper\">创建精美的信纸</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Building_blocks/A_cool_looking_box\">一个漂亮的盒子</a></li></ol></details></li><li><details><summary>样式化文本</summary><ol><li><a href=\"/zh-CN/docs/Learn/CSS/Styling_text\">为文本添加样式（样式化文本）</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Styling_text/Fundamentals\">基本文本和字体样式</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Styling_text/Styling_lists\">为列表添加样式</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Styling_text/Styling_links\">样式化链接</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Styling_text/Web_fonts\">Web 字体</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Styling_text/Typesetting_a_homepage\">作业：排版社区大学首页</a></li></ol></details></li><li><details><summary>CSS 排版</summary><ol><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout\">CSS 布局</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Introduction\">介绍 CSS 布局</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Normal_Flow\">常规流布局</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Flexbox\">弹性盒子</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Grids\">网格</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Floats\">浮动</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Positioning\">定位</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Multiple-column_Layout\">多列布局</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Responsive_Design\">响应式设计</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Media_queries\">媒体查询入门指南</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Legacy_Layout_Methods\">传统的布局方法</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Supporting_Older_Browsers\">支持旧浏览器</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/CSS_layout/Fundamental_Layout_Comprehension\">作业：基本布局理解</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/JavaScript\">JavaScript——用户端动态脚本</a></li><li><details><summary>JavaScript 第一步</summary><ol><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps\">JavaScript 第一步</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/What_is_JavaScript\">什么是 JavaScript？</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/A_first_splash\">JavaScript 初体验</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/What_went_wrong\">查找并解决 JavaScript 代码的错误</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/Variables\">如何存储你需要的信息——变量</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/Math\">JavaScript 中的基础数学 — 数字和操作符</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/Strings\">文本处理——JavaScript 中的字符串</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/Useful_string_methods\">有用的字符串方法</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/Arrays\">数组</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/First_steps/Silly_story_generator\">笑话生成器</a></li></ol></details></li><li><details><summary>JavaScript 基础</summary><ol><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks\">创建 JavaScript 代码块</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/conditionals\">在代码中做决定——条件语句</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Looping_code\">循环吧，代码</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Functions\">函数——可复用的代码块</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Build_your_own_function\">创建你自己的函数</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Return_values\">函数返回值</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Events\">事件介绍</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Event_bubbling\">事件冒泡</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks/Image_gallery\">图片库</a></li></ol></details></li><li><details><summary>JavaScript 对象介绍</summary><ol><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects\">JavaScript 对象入门</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/Basics\">JavaScript 对象基础</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/Object_prototypes\">对象原型</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/Object-oriented_programming\">面向对象编程基本概念</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/Classes_in_JavaScript\">JavaScript 中的类</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/JSON\">使用 JSON</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/Object_building_practice\">实践对象构造</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Objects/Adding_bouncing_balls_features\">为“弹球”示例添加新功能</a></li></ol></details></li><li><details open=\"\"><summary>异步 JavaScript</summary><ol><li><em><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous\" aria-current=\"page\">异步 JavaScript</a></em></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing\">异步 JavaScript 简介</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Promises\">如何使用 Promise</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Implementing_a_promise-based_API\">如何实现基于 Promise 的 API</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing_workers\">workers 简介</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Sequencing_animations\">序列动画</a></li></ol></details></li><li><details><summary>客户端 Web API</summary><ol><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs\">客户端 Web API</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Introduction\">Web API 简介</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Manipulating_documents\">操作文档</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Fetching_data\">从服务器获取数据</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Third_party_APIs\">第三方 API</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Drawing_graphics\">绘图</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Video_and_audio_APIs\">视频和音频 API</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Client-side_web_APIs/Client-side_storage\">客户端存储</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/Forms\">Web 表单——与用户数据打交道</a></li><li><details><summary>Web 表单核心</summary><ol><li><a href=\"/zh-CN/docs/Learn/Forms\">Web 表单构建块</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Your_first_form\">创建我的第一个表单</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/How_to_structure_a_web_form\">如何构建 HTML 表单</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Basic_native_form_controls\">原生表单部件</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/HTML5_input_types\">HTML5 的输入（input）类型</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Other_form_controls\">其他表单控件</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Styling_web_forms\">样式化 Web 表单</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Advanced_form_styling\">表单样式化进阶</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/UI_pseudo-classes\">UI 伪类</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Form_validation\">表单数据校验</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Sending_and_retrieving_form_data\">发送表单数据</a></li></ol></details></li><li><details><summary>Web 表单进阶</summary><ol><li><a href=\"/zh-CN/docs/Learn/Forms/How_to_build_custom_form_controls\">如何构建自定义表单控件</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Sending_forms_through_JavaScript\">使用 JavaScript 发送表单</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/Property_compatibility_table_for_form_controls\">表单控件兼容性列表</a></li><li><a href=\"/zh-CN/docs/Learn/Forms/HTML_forms_in_legacy_browsers\">旧式浏览器中的 HTML 表单</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/Accessibility\">无障碍——使每个人都能使用 Web</a></li><li><details><summary>无障碍指南</summary><ol><li><a href=\"/zh-CN/docs/Learn/Accessibility\">无障碍</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/What_is_accessibility\">什么是无障碍？</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/HTML\">HTML：无障碍的良好基础</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/CSS_and_JavaScript\">CSS 和 JavaScript 无障碍最佳实践</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/WAI-ARIA_basics\">WAI-ARIA 基础</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/Multimedia\">多媒体无障碍</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/Mobile\">移动端无障碍</a></li><li><a href=\"/zh-CN/docs/Learn/Accessibility/Accessibility_troubleshooting\">测验：无障碍疑难解答</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/Performance\">性能——使网站快速响应</a></li><li><details><summary>性能指南</summary><ol><li><a href=\"/zh-CN/docs/Learn/Performance\">Web 性能</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/why_web_performance\">Web 性能的重要性</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/What_is_web_performance\">什么是 web 性能？</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/Perceived_performance\">感知性能</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/Measuring_performance\">测量性能</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/Multimedia\">多媒体：图片</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/video\">多媒体：视频</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/JavaScript\">JavaScript 性能优化</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/HTML\">HTML 性能优化</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/CSS\">CSS 性能优化</a></li><li><a href=\"/zh-CN/docs/Learn/Performance/business_case_for_performance\">web 性能的商业案例</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/MathML\">MathML——使用 MathML 语言撰写数学表达式</a></li><li><details><summary>MathML 第一步</summary><ol><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps\">MathML 入门概述</a></li><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps/Getting_started\">MathML 使用入门</a></li><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps/Text_containers\">MathML 文本容器</a></li><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps/Fractions_and_roots\">MathML 分数和根号</a></li><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps/Scripts\">MathML 附加符号</a></li><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps/Tables\">MathML 表格</a></li><li><a href=\"/zh-CN/docs/Learn/MathML/First_steps/Three_famous_mathematical_formulas\">三个著名的数学公式</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/../Games\">游戏——开发 Web 游戏</a></li><li><details><summary>指南和基础教程</summary><ol><li><a href=\"/zh-CN/docs/Games/Introduction\">Web 游戏开发简介</a></li><li><a href=\"/zh-CN/docs/Games/Techniques\">游戏开发技术</a></li><li><a href=\"/zh-CN/docs/Games/Tutorials\">教程</a></li><li><a href=\"/zh-CN/docs/Games/Publishing_games\">发布游戏</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/Tools_and_testing\">工具与测试</a></li><li><details><summary>客户端 web 开发工具</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools\">理解客户端 web 开发工具</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Overview\">客户端工具概述</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Command_line\">命令行速成课</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Package_management\">软件包管理基础</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Introducing_complete_toolchain\">介绍完整的工具链</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Understanding_client-side_tools/Deployment\">部署我们的应用</a></li></ol></details></li><li><details><summary>客户端框架介绍</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Introduction\">客户端框架介绍</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Main_features\">框架的主要特性</a></li></ol></details></li><li><details><summary>React</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_getting_started\">React 入门</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_todo_list_beginning\">开始我们的 React 待办清单</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_components\">组件化我们的 React App</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_interactivity_events_state\">React interactivity: Events and state</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_interactivity_filtering_conditional_rendering\">React interactivity: Editing, filtering, conditional rendering</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_accessibility\">Accessibility in React</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_resources\">React resources</a></li></ol></details></li><li><details><summary>Ember</summary><ol><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_getting_started\">Getting started with Ember</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_structure_componentization\">Ember app structure and componentization</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_interactivity_events_state\">Ember interactivity: Events, classes and state</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_conditional_footer\">Ember Interactivity: Footer functionality, conditional rendering</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_routing\">Routing in Ember</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Ember_resources\">Ember resources and troubleshooting</a></li></ol></details></li><li><details><summary>Vue</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_getting_started\">开始使用 Vue</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_first_component\">创建第一个 Vue 组件</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_rendering_lists\">渲染 Vue 组件列表</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_methods_events_models\">使用 Vue event、method 和 model 添加一个新的 todo 表单</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_styling\">使用 CSS 为 Vue 组件添加样式</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_computed_properties\">Vue 中的计算属性</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_conditional_rendering\">Vue 中的条件渲染：编辑现有的待办事项</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_refs_focus_management\">使用 Vue 模板引用进行焦点管理</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Vue_resources\">Vue 资源</a></li></ol></details></li><li><details><summary>Svelte</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_getting_started\">Svelte 入门</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_Todo_list_beginning\">开始编写我们的 Svelte 待办事项列表应用程序</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_variables_props\">Svelte 中的动态行为：变量和属性</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_components\">将我们的 Svelte 应用组件化</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_reactivity_lifecycle_accessibility\">Svelte 进阶：响应式、生命周期以及无障碍</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_stores\">使用 Svelte store</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_TypeScript\">Svelte 对 TypeScript 的支持</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Svelte_deployment_next\">部署以及下一步</a></li></ol></details></li><li><details><summary>Angular</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_getting_started\">Angular 入门</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_todo_list_beginning\">Beginning our Angular todo list app</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_styling\">Styling our Angular app</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_item_component\">Creating an item component</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_filtering\">Filtering our to-do items</a></li><li><a class=\"only-in-en-us\" title=\"此页面目前仅提供英文版本\" href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/Angular_building\">Building Angular applications and further resources</a></li></ol></details></li><li><details><summary>Git 和 GitHub</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/GitHub\">Git 和 GitHub</a></li></ol></details></li><li><details><summary>跨浏览器测试</summary><ol><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing\">跨浏览器测试</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Introduction\">跨浏览器测试介绍</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Testing_strategies\">测试的策略</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/HTML_and_CSS\">处理常见的 HTML 和 CSS 问题</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/JavaScript\">处理常见的 JavaScript 问题</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Accessibility\">解决常见的无障碍问题</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Feature_detection\">实现特性检测</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Automated_testing\">自动化测试简介</a></li><li><a href=\"/zh-CN/docs/Learn/Tools_and_testing/Cross_browser_testing/Your_own_automation_environment\">搭建自己的自动化测试环境</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/Server-side\">服务端网页编程</a></li><li><details><summary>第一步</summary><ol><li><a href=\"/zh-CN/docs/Learn/Server-side/First_steps\">服务端网站编程的第一步</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/First_steps/Introduction\">服务端编程介绍</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/First_steps/Client-Server_overview\">客户端服务端交互概述</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/First_steps/Web_frameworks\">服务端 web 框架</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/First_steps/Website_security\">站点安全</a></li></ol></details></li><li><details><summary>Django Web 框架（Python）</summary><ol><li><a href=\"/zh-CN/docs/Learn/Server-side/Django\">Django Web 框架 (python)</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Introduction\">Django 介绍</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/development_environment\">设置 Django 开发环境</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Tutorial_local_library_website\">Django Tutorial: The Local Library website</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/skeleton_website\">Django Tutorial Part 2: 创建网站的地基</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Models\">Django Tutorial Part 3: 使用模型</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Admin_site\">Django Tutorial Part 4: Django 管理员站点</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Home_page\">Django 教程 5：主页构建</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Generic_views\">Django 教程 6: 通用列表和详细信息视图</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Sessions\">Django 教程 7: 会话框架</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Authentication\">Django 教程 8：用户授权与许可</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Forms\">Django 教程 9: 使用表单</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Testing\">Django 教程 10: 测试 Django 网页应用</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/Deployment\">Django 教程 11：部署 Django 到生产环境</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/web_application_security\">Django Web 应用安全</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Django/django_assessment_blog\">评估：DIY Django 微博客</a></li></ol></details></li><li><details><summary>Express Web 框架（Node.js/JavaScript）</summary><ol><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs\">Express Web 框架（Node.js/JavaScript）</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/Introduction\">Express/Node 入门</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/development_environment\">设置 Node 开发环境</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/Tutorial_local_library_website\">Express 教程：本地图书馆网站</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/skeleton_website\">Express 教程 2：创建站点框架</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/mongoose\">Express 教程 3：使用数据库 (Mongoose)</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/routes\">Express 教程 4：路由和控制器</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/Displaying_data\">Express 教程 5: 呈现图书馆数据</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/forms\">Express 教程 6: 使用表单</a></li><li><a href=\"/zh-CN/docs/Learn/Server-side/Express_Nodejs/deployment\">Express 教程 7: 部署到生产环境</a></li></ol></details></li><li class=\"section\"><a href=\"/zh-CN/docs/Learn/Common_questions\">更多资源</a></li><li><details><summary>常见问题</summary><ol><li><a href=\"/zh-CN/docs/Learn/Common_questions\">常见问题</a></li><li><a href=\"/zh-CN/docs/Learn/HTML/Howto\">使用 HTML 解决常见问题</a></li><li><a href=\"/zh-CN/docs/Learn/CSS/Howto\">解决常见的 CSS 问题</a></li><li><a href=\"/zh-CN/docs/Learn/JavaScript/Howto\">解决 JavaSctript 代码的常见问题</a></li><li><a href=\"/zh-CN/docs/Learn/Common_questions/Web_mechanics\">Web 机制</a></li><li><a href=\"/zh-CN/docs/Learn/Common_questions/Tools_and_setup\">工具和安装</a></li><li><a href=\"/zh-CN/docs/Learn/Common_questions/Design_and_accessibility\">设计与无障碍</a></li></ol></details></li></ol>","sidebarMacro":"LearnSidebar","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>在这个模块，我们将查看<a href=\"/zh-CN/docs/Glossary/Asynchronous\">异步</a> <a href=\"/zh-CN/docs/Glossary/JavaScript\">JavaScript</a>，异步为什么很重要，以及怎样使用异步来有效处理潜在的阻塞操作，比如从服务器上获取资源。</p>"}},{"type":"prose","value":{"id":"预备知识","title":"预备知识","isH3":false,"content":"<p>异步 JavaScript 是一个相当高级的话题，建议你先完成 <a href=\"/zh-CN/docs/Learn/JavaScript/First_steps\">JavaScript 第一步</a>和<a href=\"/zh-CN/docs/Learn/JavaScript/Building_blocks\">创建 JavaScript 代码块</a> 两个模块的学习后再来学习。</p>\n<div class=\"notecard note\">\n <p><strong>备注：</strong>如果你工作在一个无权创建自己文件的电脑/平板/其他设备上，你需要在一个在线编程工具上试验（大多数）代码示例，如 <a href=\"https://jsbin.com/\" class=\"external\" target=\"_blank\">JSBin</a> 或者 <a href=\"https://glitch.com\" class=\"external\" target=\"_blank\">Glitch</a>.</p>\n</div>"}},{"type":"prose","value":{"id":"指南","title":"指南","isH3":false,"content":"<dl>\n <dt id=\"异步_javascript_简介\"><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing\">异步 JavaScript 简介</a></dt>\n <dd>\n <p>在这篇文章中我们将介绍 <strong>同步编程</strong> 和 <strong>异步编程</strong> 是什么，为什么我们总是需要异步编程技术，异步函数过去是怎样在 JavaScript 上实现的，以及这些方式的问题有哪些。</p>\n </dd>\n <dt id=\"如何使用_promise\"><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Promises\">如何使用 Promise</a></dt>\n <dd>\n <p>我们将在这里介绍 Promise 并向你展示如何使用基于 Promise 的 API。我们也会介绍 <code>async</code> 和 <code>await</code> 关键字。</p>\n </dd>\n <dt id=\"应用一个基于_promise_的_api\"><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Implementing_a_promise-based_API\">应用一个基于 Promise 的 API</a></dt>\n <dd>\n <p>本文概述了如何实现一个我们自己的基于 Promise 的 API。</p>\n </dd>\n <dt id=\"worker_简介\"><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Introducing_workers\">Worker 简介</a></dt>\n <dd>\n <p>Worker 使你能够在独立的线程中运行任务来保持你的主要代码的可响应性。在这篇文章中我们将把一个长时间运行的同步函数重写为使用 Worker 的示例。</p>\n </dd>\n</dl>"}},{"type":"prose","value":{"id":"测验","title":"测验","isH3":false,"content":"<dl>\n <dt id=\"序列动画\"><a href=\"/zh-CN/docs/Learn/JavaScript/Asynchronous/Sequencing_animations\">序列动画</a></dt>\n <dd>\n <p>这个测验要求你使用 Promise 来播放一组特定序列的动画。</p>\n </dd>\n</dl>"}},{"type":"prose","value":{"id":"参见","title":"参见","isH3":false,"content":"<ul>\n <li>由 Marijn Haverbeke 编写的电子书籍 <a href=\"https://eloquentjavascript.net/\" class=\"external\" target=\"_blank\">Eloquent JavaScript</a> 中的 <a href=\"https://eloquentjavascript.net/11_async.html\" class=\"external\" target=\"_blank\">异步编程</a>。</li>\n</ul>"}}],"toc":[{"text":"预备知识","id":"预备知识"},{"text":"指南","id":"指南"},{"text":"测验","id":"测验"},{"text":"参见","id":"参见"}],"summary":"在这个模块，我们将查看异步 JavaScript，异步为什么很重要，以及怎样使用异步来有效处理潜在的阻塞操作，比如从服务器上获取资源。","popularity":0,"modified":"2024-07-27T03:21:20.000Z","other_translations":[{"locale":"de","title":"Asynchronous JavaScript","native":"Deutsch"},{"locale":"en-US","title":"Asynchronous JavaScript","native":"English (US)"},{"locale":"es","title":"JavaScript asíncrono","native":"Español"},{"locale":"fr","title":"JavaScript asynchrone","native":"Français"},{"locale":"ja","title":"非同期 JavaScript","native":"日本語"},{"locale":"ko","title":"비동기 JavaScript","native":"한국어"},{"locale":"pt-BR","title":"JavaScript Assíncrono","native":"Português (do Brasil)"},{"locale":"ru","title":"Асинхронный JavaScript","native":"Русский"},{"locale":"zh-TW","title":"非同步的 JavaScript","native":"正體中文 (繁體)"}],"pageType":"unknown","source":{"folder":"zh-cn/learn/javascript/asynchronous","github_url":"https://github.com/mdn/translated-content/blob/main/files/zh-cn/learn/javascript/asynchronous/index.md","last_commit_url":"https://github.com/mdn/translated-content/commit/6ec5a237611743b565003deb101b9edcb2f3135e","filename":"index.md"},"short_title":"异步 JavaScript","parents":[{"uri":"/zh-CN/docs/Learn","title":"学习 Web 开发"},{"uri":"/zh-CN/docs/Learn/JavaScript","title":"JavaScript——动态客户端脚本语言"},{"uri":"/zh-CN/docs/Learn/JavaScript/Asynchronous","title":"异步 JavaScript"}],"pageTitle":"异步 JavaScript - 学习 Web 开发 | MDN","noIndexing":false}}</script></body></html>