如何在react-router中使用头标记、nav

npm install react-router-dom

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

const Header = () => (
  <header>
    <nav>
      <ul>
        <li>
          <Link to="/">首页</Link>
        </li>
        <li>
          <Link to="/about">关于</Link>
        </li>
        <li>
          <Link to="/contact">联系我们</Link>
        </li>
      </ul>
    </nav>
  </header>
);

const Home = () => <h1>欢迎来到首页！</h1>;
const About = () => <h1>这是关于页面。</h1>;
const Contact = () => <h1>请通过以下方式联系我们。</h1>;

const App = () => (
  <Router>
    <div>
      <Header />
      <Route exact path="/" component={Home} />
      <Route path="/about" component={About} />
      <Route path="/contact" component={Contact} />
    </div>
  </Router>
);

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