我的内容显示正常。之后，我的内容没有显示，我不明白为什么。我也下载了React-Route-DOM.

代码

import './App.css';
import Navbar from './components/Navbar.js'
import HomeView from './components/HomeView.js'
import AboutView from './components/AboutView.js'
import {Switch, Route} from 'react-router-dom'

function App() {
  return (
    <div>
    <Switch>
    <Navbar/>
    <Route path="/" exact>
<HomeView/>
</Route>
<Route path="/about" component={AboutView}/>

</Switch>
    </div>
  );
}

export default App;

代码

const HomeView = () => {
  return(
    <div>
    <h1>Home</h1>
    </div>
  )
}

export default HomeView;

const AboutView = () => {
  return (
    <div>
    <h1>About</h1>
    </div>
  )
}

export default AboutView;

代码来自index.js

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import reportWebVitals from './reportWebVitals';
import { BrowserRouter} from 'react-router-dom';

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

顺晟科技：