在react-router-dom v6中，开关被路由替换。下面是配置react-router-dom v6的简单示例。

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

import Layout from './components/Layout';
import ProtectedRoute from './components/ProtectedRoute';
import LoginPage from './pages/LoginPage';
import WizardPage from './pages/WizardPage';
import RequestsPage from './pages/RequestsPage';

import './App.scss'

export class App extends React.Component {
    public render() {
        const sharedRouteProps = { exact: true, authenticationPath: '/login' };
        const wizardRouteProps = { ...sharedRouteProps, path: "/", component: WizardPage };
        const requestsRouteProps = { ...sharedRouteProps, path: "/requests", component: RequestsPage };

        return (
            <Layout>
              <Router>
                <Switch>
                    <Route exact path='/login' component={LoginPage} />
                    <ProtectedRoute {...wizardRouteProps} />
                    <ProtectedRoute {...requestsRouteProps} />
                </Switch>
              </Router>
            </Layout>
        );
    }
}

第一步:升级到React 16.8+和React -router-dom v5.2:

npm uninstall react-router-dom
npm install react-router-dom@5.2

步骤2:更新react-router-dom导入语句。

修改import {Switch, Route} from "react-router-dom";:

import { Routes, Route } from 'react-router-dom';

第三步:升级语法，把“Switch”换成“Routes”，把“component”换成“element”

改变

<Switch>
    <Route path="/home" component={HomePage} />
</Switch>

to

<Routes>
    <Route path="/home" element={<HomePage/>} />
</Routes>

或者，您也可以按照其他解决方案中的建议降低react-router版本。

但是，我建议升级到react-router-dom及其语法的最新版本，而不是倒退。

这是一个使用react-router-dom V6的例子

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

import '../styles/global.css'

import Layout from '../containers/Layout'
import Home from '../pages/Home'
import Login from '../containers/Login'
import RecoveryPassword from '../containers/RecoveryPassword'
import NotFound from '../pages/NotFound'

const App = () => {
  return (
    <Router>
      <Layout>
        <Routes>
          <Route exact path="/" element={<Home/>}/>
          <Route exact path="/login" element={<Login/>}/>
          <Route exact path="/recovery-password" element={<RecoveryPassword/>}/>
          <Route path="*" element={<NotFound/>}/>
        </Routes>
      </Layout>
    </Router>
  );
}

export default App;

如果你正在使用一个更新版本的react-router-dom(例如，在我的例子中是^6.2.1)，你应该将<Switch>更改为<Routes>，并使用<Route>和component={<SampleComponent />}参数。

特别是下面的代码示例:

import { BrowserRouter as Router, Routes, Route} from 'react-router-dom';
import MyComponent from './containers/MyComponent';

export default function AppRoutes() {
    return (
        <Routes>
            <Route exact path="/" component={<MyComponent />}>
            </Route>
        </Routes>
    );
}

Switch是从react-router导出的，而不是从react-router-dom导出的(我认为Route也一样)。

import React from "react";
import { Link, BrowserRouter as Router, Route, Routes } from "react-router-dom";
import "./App.css";
import App from "./App";
const RouterPage = () => {
    return (
        <Router>
            <div>
                <nav>
                    <Link to="/">Home</Link>
                    <Link to="/posts">Posts</Link>
                    <Link to="/">About</Link>
                    <Link to="/contact">Contact</Link>
                </nav>
                <Routes>
                    <Route exact path="/" element={<App />}></Route>
                    <Route path="/post" element={<App />} />
                    <Route path="/about" element={<App />} />
                    <Route path="/contact" element={<App />} />
                </Routes>
            </div>
        </Router>
    );
};

你应该把Switch换成Routes