将React Router与开关一起使用，并且在更改路由时无法让页面呈现不同的组件

npm install react-router-dom

yarn add react-router-dom

import { BrowserRouter as Router, Switch, Route, Link } from 'react-router-dom';

import Home from './Home';
import About from './About';
import Contact from './Contact';

function App() {
  return (
    <Router>
      <div>
        <nav>
          <ul>
            <li>
              <Link to="/">Home</Link>
            </li>
            <li>
              <Link to="/about">About</Link>
            </li>
            <li>
              <Link to="/contact">Contact</Link>
            </li>
          </ul>
        </nav>

        <Switch>
          <Route path="/about">
            <About />
          </Route>
          <Route path="/contact">
            <Contact />
          </Route>
          <Route path="/">
            <Home />
          </Route>
        </Switch>
      </div>
    </Router>
  );
}

function Home() {
  return <h2>Home</h2>;
}

function About() {
  return <h2>About</h2>;
}

function Contact() {
  return <h2>Contact</h2>;
}

import React, { useState } from 'react';
import { useHistory } from 'react-router-dom';

function SwitchComponent() {
  const [isSwitchOn, setSwitchOn] = useState(false);
  const history = useHistory();

  const handleSwitchToggle = () => {
    setSwitchOn(!isSwitchOn);
    if (isSwitchOn) {
      history.push('/about');
    } else {
      history.push('/contact');
    }
  };

  return (
    <div>
      <button onClick={handleSwitchToggle}>{isSwitchOn ? 'About' : 'Contact'}</button>
    </div>
  );
}