React-routes express-server

Question

我正在学习使用rect，当我尝试按照链接时，我遇到了这样的错误：

我的client.js

import React, { Component } from 'react';
import { render } from 'react-dom';
import App from '../components/first_page/App';
import {Router, Route } from 'react-router';
import { browserHistory } from 'react-router';

class Main extends Component {
    render(){
        return (
          <Router>
            <Route history = {browserHistory}>
                <Route path="/f" component={App}/>
            </Route>
        </Router>
        );
    }
}
render (<Main />, window.document.getElementById('app'))

App.js

import React, { Component } from 'react';
import Bootstrap from 'bootstrap/dist/css/bootstrap.css';
import { Button } from 'react-bootstrap';
class App extends Component{
  render(){
      return (
        <div>
         <Button>Start!</Button>
          <Button>Login!</Button>
        </div>
      );
  }
}
export default App

服务器

  var express = require('express');
var path = require('path');
var config = require('../webpack.config.js');
var webpack = require('webpack');


var webpackDevMiddleware = require('webpack-dev-middleware');
var webpackHotMiddleware = require('webpack-hot-middleware');

var app = express()
var compiler = webpack(config);
app.use(webpackDevMiddleware(compiler, {noInfo: true, publicPath: config.output.publicPath}));
app.use(webpackHotMiddleware(compiler));


app.use(express.static(path.resolve(__dirname, './dist')));

app.use('/', function (req, res) {
    res.sendFile(path.resolve('client/index.html'));
});
var port = process.env.PORT || 4000;

app.listen(port, function(error) {
  if (error) throw error;
  console.log("Express server listening on port", port);
});

我试图通过不同的教程，但总是会得到这些错误，我会很高兴有任何帮助，谢谢