React-router在嵌套组件中加载组件

npm install react-router-dom

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

render() {
  return (
    <Router>
      <Switch>
        <Route exact path="/" component={Home} />
        <Route path="/about" component={About} />
        <Route path="/contact" component={Contact} />
      </Switch>
    </Router>
  );
}

import { Link } from 'react-router-dom';

class Navbar extends React.Component {
  render() {
    return (
      <nav>
        <ul>
          <li><Link to="/">Home</Link></li>
          <li><Link to="/about">About</Link></li>
          <li><Link to="/contact">Contact</Link></li>
        </ul>
      </nav>
    );
  }
}