React DOM API

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API

这些 API 可以从你的组件中导入。它们很少被使用：

¥These APIs can be imported from your components. They are rarely used:

• createPortal 允许你在 DOM 树的不同部分渲染子组件。

  ¥createPortal lets you render child components in a different part of the DOM tree.

• flushSync 允许你强制 React 刷新状态更新并同步更新 DOM。

  ¥flushSync lets you force React to flush a state update and update the DOM synchronously.

资源预加载 API

¥Resource Preloading APIs

这些 API 可用于在你知道需要时立即预加载脚本、样式表和字体等资源，例如在导航到将使用资源的另一个页面之前，从而使应用运行得更快。

¥These APIs can be used to make apps faster by pre-loading resources such as scripts, stylesheets, and fonts as soon as you know you need them, for example before navigating to another page where the resources will be used.

基于 React 的框架 经常为你处理资源加载，因此你可能不必自己调用这些 API。有关详细信息，请参阅你的框架的文档。

¥React-based frameworks frequently handle resource loading for you, so you might not have to call these APIs yourself. Consult your framework’s documentation for details.

• prefetchDNS 允许你预取你希望连接到的 DNS 域名的 IP 地址。

  ¥prefetchDNS lets you prefetch the IP address of a DNS domain name that you expect to connect to.

• preconnect 允许你连接到你希望从中请求资源的服务器，即使你还不知道需要什么资源。

  ¥preconnect lets you connect to a server you expect to request resources from, even if you don’t know what resources you’ll need yet.

• preload 允许你获取你希望使用的样式表、字体、图片或外部脚本。

  ¥preload lets you fetch a stylesheet, font, image, or external script that you expect to use.

• preloadModule 允许你获取你希望使用的 ESM 模块。

  ¥preloadModule lets you fetch an ESM module that you expect to use.

• preinit 允许你获取并评估外部脚本或获取并插入样式表。

  ¥preinit lets you fetch and evaluate an external script or fetch and insert a stylesheet.

• preinitModule 允许你获取并评估 ESM 模块。

  ¥preinitModule lets you fetch and evaluate an ESM module.

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入口点

¥Entry points

react-dom 包提供了两个额外的入口点：

¥The react-dom package provides two additional entry points:

• react-dom/client 包含在客户端（在浏览器中）渲染 React 组件的 API。

  ¥react-dom/client contains APIs to render React components on the client (in the browser).

• react-dom/server 包含用于在服务器上渲染 React 组件的 API。

  ¥react-dom/server contains APIs to render React components on the server.

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已删除的 API

¥Removed APIs

这些 API 在 React 19 中被删除：

¥These APIs were removed in React 19:

• findDOMNode：参见 alternatives。

  ¥findDOMNode: see alternatives.

• hydrate：改用 hydrateRoot。

  ¥hydrate: use hydrateRoot instead.

• render：改用 createRoot。

  ¥render: use createRoot instead.

• unmountComponentAtNode：改用 root.unmount()。

  ¥unmountComponentAtNode: use root.unmount() instead.

• renderToNodeStream：改用 react-dom/server API。

  ¥renderToNodeStream: use react-dom/server APIs instead.

• renderToStaticNodeStream：改用 react-dom/server API。

  ¥renderToStaticNodeStream: use react-dom/server APIs instead.