你來百度搜索這個問題就說明你就沒好好的看人家提供的README.md檔案

這上面說的很清楚，如何安裝、如何使用，刪除src/App.js,開啟這個連結複製貼貼就OK了，我們來掩飾一遍

1.執行 npm install --save react-router-dom 或者 yarn add react-router-dom 根據自己的實際情況選擇

2.然後找到src/App.js 刪除掉裡面所有的 ，複製我下面的程式碼

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

const BasicExample = () => (
  <Router>
    //這裡是靜態樣式
    <div>
      <ul>
        <li>
          <Link to="/">Home</Link>
        </li>
        <li>
          <Link to="/about">About</Link>
        </li>
        <li>
          <Link to="/topics">Topics</Link>
        </li>
      </ul>

      <hr />
      //這裡是配飾路由的地方(核心)
      <Route exact path="/" component={Home} />
      <Route path="/about" component={About} />
      <Route path="/topics" component={Topics} />
    </div>
  </Router>
);
//子元件 Home
const Home = () => (
  <div>
    <h2>Home</h2>
  </div>
);
//子元件 About
const About = () => (
  <div>
    <h2>About</h2>
  </div>
);
// 子元件 Topics
const Topics = ({ match }) => (
  <div>
    <h2>Topics</h2>
    <ul>
      <li>
        <Link to={`${match.url}/rendering`}>Rendering with React</Link>
      </li>
      <li>
        <Link to={`${match.url}/components`}>Components</Link>
      </li>
      <li>
        <Link to={`${match.url}/props-v-state`}>Props v. State</Link>
      </li>
    </ul>

    <Route path={`${match.path}/:topicId`} component={Topic} />
    <Route
      exact
      path={match.path}
      render={() => <h3>Please select a topic.</h3>}
    />
  </div>
);

const Topic = ({ match }) => (
  <div>
    <h3>{match.params.topicId}</h3>
  </div>
);

export default BasicExample;
 

刪掉我的註釋，直接暴力複製貼貼，怎麼樣解決了嗎