const Component = React.Component;
        const Router = window.ReactRouterDOM.HashRouter;
        const Route = window.ReactRouterDOM.Route;
        const Link = window.ReactRouterDOM.Link;
        const Prompt = window.ReactRouterDOM.Prompt;
        const Switch = window.ReactRouterDOM.Switch;
        const Redirect = window.ReactRouterDOM.Redirect;
        //const createHashHistory=win
        //antd
        const Button = antd.Button;

        class Home extends Component {
            render() {
                return (
                    <div>
                        <h2>
                            <Button type="primary">Home</Button>
                        </h2>
                    </div>
                )
            }
        }

        const About = () => (
            <div>
                <h2>About</h2>
            </div>
        )

        const Product = () => (
            <div>
                <h2>Product</h2>
            </div>
        )

        class App extends Component {
            render() {
                return (
                    <Router>
                        <div className="App">
                            <Link to="/">Home</Link>
                            <Link to="/About">About</Link>
                            <Link to="/Product">Product</Link>
                            <hr />
                            <Route path="/" exact component={Home}></Route>
                            <Route path="/about" component={About}></Route>
                            <Route path="/product" component={Product}></Route>
                        </div>
                    </Router>
                );
            }
        }

        ReactDOM.render(
            <App />
            ,
            document.getElementById('app')
        );