React 反应
The library for web and native user interfaces
用于网页和本地用户界面的库
Create user interfaces from components
从组件创建用户界面
React lets you build user interfaces out of individual pieces called components. Create your own React components like Thumbnail, LikeButton, and Video. Then combine them into entire screens, pages, and apps.
React 让你可以通过称为组件的单个部分构建用户界面。创建你自己的 React 组件，如 Thumbnail、LikeButton 和 Video。然后将它们组合成完整的屏幕、页面和应用程序。
Whether you work on your own or with thousands of other developers, using React feels the same. It is designed to let you seamlessly combine components written by independent people, teams, and organizations.
无论你是独自工作还是与成千上万的其他开发者一起，使用 React 的感觉都是一样的。它旨在让你无缝地组合由独立个人、团队和组织编写的组件。
Write components with code and markup
用代码和标记编写组件
React components are JavaScript functions. Want to show some content conditionally? Use an if statement. Displaying a list? Try array map(). Learning React is learning programming.
React 组件是 JavaScript 函数。想要有条件地显示一些内容吗？使用 if 语句。要显示一个列表？试试数组 map()。学习 React 就是学习编程。
This markup syntax is called JSX. It is a JavaScript syntax extension popularized by React. Putting JSX markup close to related rendering logic makes React components easy to create, maintain, and delete.
这种标记语法称为 JSX。它是由 React 推广的 JavaScript 语法扩展。将 JSX 标记与相关的渲染逻辑放在一起，使得 React 组件易于创建、维护和删除。
Add interactivity wherever you need it
在需要的地方添加互动性
React components receive data and return what should appear on the screen. You can pass them new data in response to an interaction, like when the user types into an input. React will then update the screen to match the new data.
React 组件接收数据并返回应该在屏幕上显示的内容。您可以在用户输入时将新数据传递给它们，作为对交互的响应。然后，React 将更新屏幕以匹配新数据。
You don’t have to build your whole page in React. Add React to your existing HTML page, and render interactive React components anywhere on it.
Go full-stack
with a framework
React is a library. It lets you put components together, but it doesn’t prescribe how to do routing and data fetching. To build an entire app with React, we recommend a full-stack React framework like Next.js or Remix.
confs/[slug].js
import { db } from './database.js';
import { Suspense } from 'react';
async function ConferencePage({ slug }) {
const conf = await db.Confs.find({ slug });
return (
<ConferenceLayout conf={conf}>
<Suspense fallback={<TalksLoading />}>
<Talks confId={conf.id} />
</Suspense>
</ConferenceLayout>
);
}
async function Talks({ confId }) {
const talks = await db.Talks.findAll({ confId });
const videos = talks.map(talk => talk.video);
return <SearchableVideoList videos={videos} />;
}
19 Videos
React is also an architecture. Frameworks that implement it let you fetch data in asynchronous components that run on the server or even during the build. Read data from a file or a database, and pass it down to your interactive components.
Use the best from every platform
People love web and native apps for different reasons. React lets you build both web apps and native apps using the same skills. It leans upon each platform’s unique strengths to let your interfaces feel just right on every platform.
Stay true to the web
People expect web app pages to load fast. On the server, React lets you start streaming HTML while you’re still fetching data, progressively filling in the remaining content before any JavaScript code loads. On the client, React can use standard web APIs to keep your UI responsive even in the middle of rendering.
Go truly native
People expect native apps to look and feel like their platform. React Native and Expo let you build apps in React for Android, iOS, and more. They look and feel native because their UIs are truly native. It’s not a web view—your React components render real Android and iOS views provided by the platform.
With React, you can be a web and a native developer. Your team can ship to many platforms without sacrificing the user experience. Your organization can bridge the platform silos, and form teams that own entire features end-to-end.
Upgrade when the future is ready
React approaches changes with care. Every React commit is tested on business-critical surfaces with over a billion users. Over 100,000 React components at Meta help validate every migration strategy.
The React team is always researching how to improve React. Some research takes years to pay off. React has a high bar for taking a research idea into production. Only proven approaches become a part of React.
Join a community
of millions
You’re not alone. Two million developers from all over the world visit the React docs every month. React is something that people and teams can agree on.
This is why React is more than a library, an architecture, or even an ecosystem. React is a community. It’s a place where you can ask for help, find opportunities, and meet new friends. You will meet both developers and designers, beginners and experts, researchers and artists, teachers and students. Our backgrounds may be very different, but React lets us all create user interfaces together.
