反应路由器不渲染组件

Question

我正在尝试学习反应路线配置。我在一个地方添加了所有导航链接，这是入口点index.js，我的期望是当有人对导航期间配置的路径作出反应时，应该在briwser中加载相应的组件。我在我的输入文件index.js中添加了所有路径路径，如下所示：

import React from 'react';
import ReactDOM from 'react-dom';
import App from './app.js';
import { BrowserRouter, Route, hashHistory } from 'react-router-dom';
import AboutUs from './AboutUs.js';
import ContactUs from './ContactUs.js';
import {Switch} from 'react-router';

ReactDOM.render(
  (<BrowserRouter>
     <Switch>
          <Route path="/" component={App}/>
          <Route path="/about-us" component={AboutUs}/>
          <Route path="/contact-us" component={ContactUs}/>
     </Switch>
   </BrowserRouter>)
, document.getElementById('app'));

app.js如下：

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

class App extends Component {

  constructor(props){
    super(props);

  }


  render() {
   return (
     <div>
       <h1>React Router Tutorial</h1>
       <ul role="nav">
         <li><Link to="/about-us">About</Link></li>
         <li><Link to="/contact-us">Contact</Link></li>
       </ul>
     </div>
   )
 }

}
export default App;

AboutUs.js如下：

import React, { Component } from 'react';

class AboutUs extends Component {

  render(){
    return(
      <div>
        AboutUs
      </div>
    );
  }
}

export default AboutUs ;

ContactUs.js如下：

import React, { Component } from 'react';

class ContactUs extends Component{

  render(){
    return(
      <div>
        Contact Us
      </div>
    );
  }
}

export default ContactUs;

但是当我点击任何链接/ about-us或/ contact-us时，它不会加载任何内容并显示相同的app.js，如下所示

有人可以告诉我为什么会这样吗？

Answer 1

Switch renders the first route that it matches in the order that it is given.

<BrowserRouter>
  <Switch>
       <Route path="/about-us" component={AboutUs}/>
       <Route path="/contact-us" component={ContactUs}/>
       <Route path="/" component={App}/>
  </Switch>
</BrowserRouter>

Because you had given '/' as first route, anything would match it and render App component.

Answer 2

我相信它匹配您的第一个路线App，因为您没有指定它应该是exact。

你可以这样做：

<Switch>
          <Route exact path="/" component={App}/> // it will match only for '/'
          <Route path="/about-us" component={AboutUs}/>
          <Route path="/contact-us" component={ContactUs}/>
</Switch>