import React from 'react';

function useTitle(title: string): void => {
  React.useEffect(() => {
    const prevTitle = document.title;
    document.title = title;

    return () => {
      document.title = prevTitle;
    };
  }, []);
}

function MyComponent(): JSX.Element => {
  useTitle('Title while MyComponent is mounted');

  return <div>My Component</div>;
}

这是一个非常直接的解决方案，useTitle设置文档标题，当组件卸载时，它被重置为之前的任何内容。

你可以简单地在js文件中创建一个函数，并将其导出到组件中使用

像下图:

export default function setTitle(title) {
  if (typeof title !== "string") {
     throw new Error("Title should be an string");
  }
  document.title = title;
}

并像这样在任何组件中使用它:

import React, { Component } from 'react';
import setTitle from './setTitle.js' // no need to js extension at the end

class App extends Component {
  componentDidMount() {
    setTitle("i am a new title");
  }

  render() {
    return (
      <div>
        see the title
      </div>
    );
  }
}

export default App

如果你想知道，你可以直接在渲染函数中设置它:

import React from 'react';
import ReactDOM from 'react-dom';

class App extends React.Component {
    render() {
        document.title = 'wow'
        return <p>Hello</p>
    }
}

ReactDOM.render(
    <App />,
    document.getElementById('root')
)

对于功能组件:

function App() {
    document.title = 'wow'
    return <p>Hello</p>
}

但是，这是一个不好的做法，因为它会阻塞渲染(React优先考虑渲染)。

好的做法:

类组件:

class App extends React.Component {
    // you can also use componentDidUpdate() if the title is not static
    componentDidMount(){
        document.title = "good"
    }

    render() {
        return <p>Hello</p>
    }
}

功能组件:

function App() {
    // for static title, pass an empty array as the second argument
    // for dynamic title, put the dynamic values inside the array
    // see: https://reactjs.org/docs/hooks-effect.html#tip-optimizing-performance-by-skipping-effects
    useEffect(() => {
        document.title = 'good'
    }, []);

    return <p>Hello</p>
}

对于React 16.8+，你可以在函数组件中使用Effect Hook:

import React, { useEffect } from 'react';

function Example() {
  useEffect(() => {
    document.title = 'My Page Title';
  }, []);
}

要以声明的方式管理所有有效的头部标签，包括<title>，你可以使用React Helmet组件:

import React from 'react';
import { Helmet } from 'react-helmet';

const TITLE = 'My Page Title';

class MyComponent extends React.PureComponent {
  render () {
    return (
      <>
        <Helmet>
          <title>{ TITLE }</title>
        </Helmet>
        ...
      </>
    )
  }
}

import React from 'react';

function useTitle(title: string): void => {
  React.useEffect(() => {
    const prevTitle = document.title;
    document.title = title;

    return () => {
      document.title = prevTitle;
    };
  }, []);
}

function MyComponent(): JSX.Element => {
  useTitle('Title while MyComponent is mounted');

  return <div>My Component</div>;
}

这是一个非常直接的解决方案，useTitle设置文档标题，当组件卸载时，它被重置为之前的任何内容。

你可以使用下面的文档。title = '主页'

import React from 'react'
import { Component } from 'react-dom'


class App extends Component{
  componentDidMount(){
    document.title = "Home Page"
  }

  render(){
    return(
      <p> Title is now equal to Home Page </p>
    )
  }
}

ReactDOM.render(
  <App />,
  document.getElementById('root')
);

或者你可以使用这个npm包npm i react-document-title

import React from 'react'
import { Component } from 'react-dom'
import DocumentTitle from 'react-document-title';


class App extends Component{


  render(){
    return(
      <DocumentTitle title='Home'>
        <h1>Home, sweet home.</h1>
      </DocumentTitle>
    )
  }
}

ReactDOM.render(
  <App />,
  document.getElementById('root')
);

编码快乐! !