自定义文件

自定义 Document 可以更新用于渲染页面的 <html> 和 <body> 标签。

¥A custom Document can update the <html> and <body> tags used to render a Page.

要覆盖默认的 Document，请创建文件 pages/_document，如下所示：

¥To override the default Document, create the file pages/_document as shown below:

import { Html, Head, Main, NextScript } from 'next/document'

export default function Document() {
  return (
    <Html lang="en">
      <Head />
      <body>
        <Main />
        <NextScript />
      </body>
    </Html>
  )
}

import { Html, Head, Main, NextScript } from 'next/document'

export default function Document() {
  return (
    <Html lang="en">
      <Head />
      <body>
        <Main />
        <NextScript />
      </body>
    </Html>
  )
}

很高兴知道：

¥Good to know:

_document 仅在服务器上渲染，因此不能在该文件中使用像 onClick 这样的事件处理程序。

¥_document is only rendered on the server, so event handlers like onClick cannot be used in this file.

页面正确渲染需要 <Html>、<Head />、<Main /> 和 <NextScript />。

¥<Html>, <Head />, <Main /> and <NextScript /> are required for the page to be properly rendered.

注意事项

¥Caveats

_document 中使用的 <Head /> 组件与 next/head 不同。此处使用的 <Head /> 组件只能用于所有页面通用的任何 <head> 代码。对于所有其他情况，例如 <title> 标签，我们建议在你的页面或组件中使用 next/head。

¥The <Head /> component used in _document is not the same as next/head. The <Head /> component used here should only be used for any <head> code that is common for all pages. For all other cases, such as <title> tags, we recommend using next/head in your pages or components.
<Main /> 之外的 React 组件不会被浏览器初始化。不要在此处添加应用逻辑或自定义 CSS（如 styled-jsx）。如果你需要在所有页面中共享组件（例如菜单或工具栏），请阅读布局。

¥React components outside of <Main /> will not be initialized by the browser. Do not add application logic here or custom CSS (like styled-jsx). If you need shared components in all your pages (like a menu or a toolbar), read Layouts instead.
Document 目前不支持 Next.js 数据获取方法，如 getStaticProps 或 getServerSideProps。

¥Document currently does not support Next.js Data Fetching methods like getStaticProps or getServerSideProps.

自定义 `renderPage`

¥Customizing renderPage

自定义 renderPage 是高级的，只有像 CSS-in-JS 这样的库才需要支持服务器端渲染。内置 styled-jsx 支持不需要这样做。

¥Customizing renderPage is advanced and only needed for libraries like CSS-in-JS to support server-side rendering. This is not needed for built-in styled-jsx support.

我们不建议使用此模式。相反，请将逐步采用视为应用路由，它允许你更轻松地获取页面和布局的数据。

¥We do not recommend using this pattern. Instead, consider incrementally adopting the App Router, which allows you to more easily fetch data for pages and layouts.

import Document, {
  Html,
  Head,
  Main,
  NextScript,
  DocumentContext,
  DocumentInitialProps,
} from 'next/document'

class MyDocument extends Document {
  static async getInitialProps(
    ctx: DocumentContext
  ): Promise<DocumentInitialProps> {
    const originalRenderPage = ctx.renderPage

    // Run the React rendering logic synchronously
    ctx.renderPage = () =>
      originalRenderPage({
        // Useful for wrapping the whole react tree
        enhanceApp: (App) => App,
        // Useful for wrapping in a per-page basis
        enhanceComponent: (Component) => Component,
      })

    // Run the parent `getInitialProps`, it now includes the custom `renderPage`
    const initialProps = await Document.getInitialProps(ctx)

    return initialProps
  }

  render() {
    return (
      <Html lang="en">
        <Head />
        <body>
          <Main />
          <NextScript />
        </body>
      </Html>
    )
  }
}

export default MyDocument

import Document, { Html, Head, Main, NextScript } from 'next/document'

class MyDocument extends Document {
  static async getInitialProps(ctx) {
    const originalRenderPage = ctx.renderPage

    // Run the React rendering logic synchronously
    ctx.renderPage = () =>
      originalRenderPage({
        // Useful for wrapping the whole react tree
        enhanceApp: (App) => App,
        // Useful for wrapping in a per-page basis
        enhanceComponent: (Component) => Component,
      })

    // Run the parent `getInitialProps`, it now includes the custom `renderPage`
    const initialProps = await Document.getInitialProps(ctx)

    return initialProps
  }

  render() {
    return (
      <Html lang="en">
        <Head />
        <body>
          <Main />
          <NextScript />
        </body>
      </Html>
    )
  }
}

export default MyDocument

很高兴知道：

¥Good to know:

在客户端转换期间不会调用 _document 中的 getInitialProps。

¥getInitialProps in _document is not called during client-side transitions.

_document 的 ctx 对象相当于 getInitialProps 中收到的对象，并添加了 renderPage。

¥The ctx object for _document is equivalent to the one received in getInitialProps, with the addition of renderPage.

注意事项​

自定义 renderPage​

注意事项

自定义 `renderPage`