npm install -g create-react-app
create-react-app demo-app
cd demo-app

npm install react-router-dom

import React from "react";
import { BrowserRouter as Router, Route, Link } from "react-router-dom";function Index() {return <h2>Home</h2>;
}function About() {return <h2>About</h2>;
}function Users() {return <h2>Users</h2>;
}function AppRouter() {return (<Router><div><nav><ul><li><Link to="/">Home</Link></li><li><Link to="/about/">About</Link></li><li><Link to="/users/">Users</Link></li></ul></nav><Route path="/" exact component={Index} /><Route path="/about/" component={About} /><Route path="/users/" component={Users} /></div></Router>);
}export default AppRouter;

import React from "react";
import { BrowserRouter as Router, Route, Link } from "react-router-dom";function App() {return (<Router><div><Header /><Route exact path="/" component={Home} /><Route path="/about" component={About} /><Route path="/topics" component={Topics} /></div></Router>);
}function Home() {return <h2>Home</h2>;
}function About() {return <h2>About</h2>;
}function Topic({ match }) {return <h3>Requested Param: {match.params.id}</h3>;
}function Topics({ match }) {return (<div><h2>Topics</h2><ul><li><Link to={`${match.url}/components`}>Components</Link></li><li><Link to={`${match.url}/props-v-state`}>Props v. State</Link></li></ul><Route path={`${match.path}/:id`} component={Topic} /><Routeexactpath={match.path}render={() => <h3>Please select a topic.</h3>}/></div>);
}function Header() {return (<ul><li><Link to="/">Home</Link></li><li><Link to="/about">About</Link></li><li><Link to="/topics">Topics</Link></li></ul>);
}export default App;目录