import Login from '../view/Login.js';
import System from '../view/System.js';
import Bus from '../view/Bus.js';
import Bus22 from '../view/Bus22.js';

const routes = [
  {
    path: "/",component: Login,exact: true"/system/bus"default routes;

import routes from './config';
import React,{Component} from 'react';
import {
  BrowserRouter as Router,Switch,Route,Redirect,} from "react-router-dom";

/*一级路由*/
class First extends Component {
  render() {
    return (
      <Router>
        <Switch>
          {routes.map((route,i) => {
              if (route.auth) {//根据配置是否检测登录
                 (
                  <PrivateRoute key={i} path={route.path}>
                    <route.component/>
                  </PrivateRoute>
                )
              } else {
                return (<RouteWithSubRoutes key={i} {...route} />)
              }
            }
          )}
        </Switch>
      </Router>
    );
  }
}
二级路由
class SystemRouter extends Component {
  render() {
     (
        <Switch>
          {routes[1].routes.map((route,i) => {
            根据配置是否检测登录
               (
                <PrivateRoute  key={i} path={route.path}>
                  <route.component/>
                </PrivateRoute>
              )
            }             }
          })}
        </Switch>
    );
  }
}

export {
  First,SystemRouter
};
 A special wrapper for <Route> that knows how to
// handle "sub"-routes by passing them in a `routes` prop to the component it renders.
/*开放路由*/
function RouteWithSubRoutes(route) {
   (
    <Route
      exact={route.exact}
      path={route.path}
      render={props => (
         pass the sub-routes down to keep nesting
        <route.component {...props} routes={route.routes}/>
      )}
    />
  );
}
登录检测路由 PrivateRoute({children,...rest}) {
  let isAuthenticated = sessionStorage.auth;
  Route
      {...rest}
      render={({location}) =>
        isAuthenticated ? (
          children
        ) : (
          <Redirect
            to={{
              pathname: "/"        )
      }
    />
  );
}

import React from 'react';
import './App.css';
import {First} from './router/index' App() {
   (
    <First/>
  );
}

export default App;

import React,{Component} from 'react';
import {SystemRouter} from '../router/index';
import {
  withRouter
} from "react-router-dom";
import { Menu,Icon } from 'antd';

const { SubMenu } = Menu;
class System extends Component  {
  componentDidMount() {

  }

  handleClick = e => {
    this.props.history.push(e.key)
  };
  render() {
     (
      <div>
        <header>
          嵌套路由
        </header>
        <Menu
          onClick={.handleClick}
          style={{ width: 256,float:'left' }}
          defaultSelectedKeys={['1']}
          defaultOpenKeys={['sub1']}
          mode="inline"
        >
          <SubMenu
            key="sub1"
            title={
              <span>
              <Icon type="mail" />
              <span>Navigation One</span>
            </span>
            }
          >
            <Menu.Item key="/system/bus">bus</Menu.Item>
            <Menu.Item key="/system/bus22">bus22</Menu.Item>
          </SubMenu>
      
        </Menu>
        <SystemRouter  style={{ float:'left' }}/>
      </div>
    );
  }
}
export default withRouter(System);