React 4 Router error =类型是无效的预期字符串，但未定义

Question

Have a pretty straight forward React Question, I am trying to do some straight forward routing. Home page, profile page, 404 page. But keep getting the same error.

My components appear to be working as I have rendered them out successfully, however soon as I try to implement routing I get the following error.

Error: Warning: React.createElement: type is invalid -- expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in. Check the render method of Root. Warning: React.createElement: type is invalid -- expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in. Check the render method of Root.

I have gotten routes to work like this previously (react router v 4.0.0) so Im not sure what mistake I am making here. Any push in the right direction would be appreciated. Thanks in advance.

App.js

import React, { Component } from 'react';
import ReactDOM, { render } from 'react-dom';
import { BrowserRouter as Router, Match, Miss } from 'react-router';

//Components
import Home from './components/Home';
import Profile from './components/Profile';
import NotFound from './components/NotFound';

const Routes = () => {
    return (
        <Router>
            <div>
                <Match exactly pattern="/" component={Home} />
                <Match exactly pattern="/profile/:profileId" component={Profile} />
                <Miss component={NotFound} />
            </div>
        </Router>
    )
}

render(<Routes />, document.querySelector('#container')); 

Home component

import React, { Component } from 'react';

class Home extends Component {
    render() {
        return (
            <p>Home Page</p>
        )
    }
}

export default Home;

Profile component

import React, { Component } from 'react';

class Profile extends Component {
    render() {
        return (
            <p>Profile Page</p>
        )
    }
}

export default Profile;

Package.json

  "dependencies": {
    "html-webpack-plugin": "^2.28.0",
    "react": "^15.5.4",
    "react-dom": "^15.5.4",
    "react-router": "^4.1.1",
    "webpack": "^2.5.1",
    "webpack-dev-server": "^2.4.5"
  },
  "devDependencies": {
    "babel-core": "^6.24.1",
    "babel-loader": "^7.0.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-react": "^6.24.1"
  }

enter image description here

Answer 1

In App.js you should change this:

<Router>
    <div>
        <Match exactly pattern="/" component={Home} />
        <Match exactly pattern="/profile/:profileId" component={Profile} />
        <Miss component={NotFound} />
    </div>
</Router>

To this

<Router>
    <Switch>
        <Route path="/" exact component={Home} />
        <Route path="/profile/:profileId" exact component={Profile}" />
        <Route component={NotFound} />
    </Switch>
</Router>

The Switch element is used to stop verifying the other routes when one of them has made render.

And don't forget to import these modules ( Route , Switch and BrowserRouter ) from react-router-dom instead of react-router .