React使用Context与router实现权限路由详细介绍

/*
 * 资源路径 ./src/utils/PermissionContext.js
 */
import { createContext } from "react";
const PermissionContext = createContext()
export const PermissionContextProvider = PermissionContext.Provider
export const PermissionContextConsumer = PermissionContext.Consumer
export default PermissionContext

/*
 * 资源路径 ./src/components/PermissionIndex.js
 */
import React, { useState, useEffect } from 'react'
import { PermissionContextProvider } from '../../utils/PermissionContext' // import对应的Context
function PermissionIndex(Component) {
  return function Index(props){
    const [permission, setpermission] = useState([])
    useEffect(()=>{
		setpermission(['cart'])
		//此处实际为 获取权限列表的请求操作
	},[])
	//代替了类组件的componenetDidMount生命周期
    return (
      <PermissionContextProvider value={permission}>
        <Component {...props}></Component>
      </PermissionContextProvider>
      //此处返回了注入权限列表Context的组件
    )
  }
}
export default PermissionIndex

/*
 * 资源路径 ./src/components/PermissionRoute.js
 */
import {useContext} from "react";
import PermissionContext from "../utils/PermissionContext";
import {Redirect, Route} from "react-router-dom";
function PermissionRoute(props){
    const context = useContext(PermissionContext)
    return (
        context.indexOf(props.permission) > -1 ?
            <Route
                path={props.path}
                exact={props.exact}
                strict={props.strict}
                sensitive={props.sensitive}
                render={prop => props.render ? props.render({...prop}) : <props.component {...props}/>}
            /> :
            <Redirect from={'/props.path'} to={"/403"}/>
    )
}
export default PermissionRoute;

/*
 * 资源路径 ./src/App.js
 */
import React from 'react';
import {Redirect, Route, Switch} from 'react-router-dom';
import Page1 from "./pages/Page1";
import Page2 from "./pages/Page2";
import Page3 from "./pages/Page3";
import Error from "./pages/Error"; // 无页面时显示的404页面
import PermissionIndex from "./components/PermissionIndex";
import PermissionRoute from "./components/PermissionRoute";
import NoPermission from "./pages/NoPermission"; // 无权限时显示的页面
/*
 * 利用es7的decorator实现高阶组件
 * 此处等价于：
 * class App extends React.Component {
 *   render(){}
 * }
 * const App = PermissionIndex(App)
 * export default App
 */
@PermissionIndex
export default class App extends React.Component{
    render() {
        return (
            <div>
                <Switch>
                    <Route path={'/page1'} component={Page1}/>
                    <PermissionRoute path={'/page2'} component={Page2} permission={"cart"}/>
                    <Route path={'/page3'} component={Page3}/>
                    <Route path={'/404'} component={Error}/>
                    <Route path={'/403'} component={NoPermission}/>
                    <Redirect to={'/404'}/>
                </Switch>
            </div>
        );
    }
}

/*
 * 资源路径 ./src/index.js
 */
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import {BrowserRouter} from "react-router-dom";
ReactDOM.render(
  <React.StrictMode>
      <BrowserRouter>
          <App></App>
      </BrowserRouter>
  </React.StrictMode>,
  document.getElementById('root')
);

/*
 * 资源路径 ./src/components/permissionRouterConfig.js
 */
import {Redirect, Route, Switch} from "react-router-dom";
import React, {useContext} from "react";
import PermissionContext from "../utils/PermissionContext";
// extraParams 绑定到路由组件的其他参数
// switchParams 绑定到Switch组件的其他参数
function permissionRouterConfig(routes, extraParams = {}, switchParams = {}){
    // 此处返回一个React组件，但此处不属于高阶组件
    return function PRC(){
        const context = useContext(PermissionContext)
        return routes ? (
            <Switch {...switchParams}>
                {
          					// 遍历传入的routes数组
                    routes.map((route,index)=>(
                      	/*
                         * 通过Array.prototype.indexOf() 方法判断权限是否在权限列表中
                         * 通过withPermission参数判断该路由是否需要进行权限拦截
                         */
                        (context.indexOf(route.permission) > -1 || !route.withPermission) ?
                        <Route
                            key={route.key || index}
                            path={route.path}
                            exact={route.exact}
                            sensitive={route.sensitive}
                            strict={route.strict}
                            render={props=>route.render?(route.render({...props, ...extraParams})) : (<route.component {...props} {...extraParams}/>)}
                        /> :
                        <Redirect from={route.path} to={'/403'}/>
                        // 当权限列表中存在权限或不需要权限拦截时，渲染路由组件；否则渲染重定向组件
                    ))
                }
            </Switch>
        ) : null
    }
}
export default permissionRouterConfig

/*
 * 资源路径 ./src/App.js
 */
import React from 'react';
import {Redirect, Route, Switch} from 'react-router-dom';
import Page1 from "./pages/Page1";
import Page2 from "./pages/Page2";
import Page3 from "./pages/Page3";
import Error from "./pages/Error";
import PermissionIndex from "./components/PermissionIndex";
import NoPermission from "./pages/NoPermission";
import permissionRouterConfig from "./components/permissionRouterConfig";
const routes = [{
    path: '/page1',
    component: Page1,
    withPermission: true, // withPermission为true，启用权限拦截
    permission: "cart" // 访问该页面所需的权限名
},{
    path: '/page2',
    render: props=><Page2 {...props}></Page2>
},{
    path: '/page3',
    component: Page3,
    withPermission: false // withPermission为false或undefined,不启用权限拦截
},{
    path: '/404',
    component: Error
},{
    path: '/403',
    component: NoPermission
},{
    path: '/',
    render: ()=><Redirect to={'/404'}/>
}]
const PermissionRouter = permissionRouterConfig(routes)
// 传入routes规则，返回一个包含Switch和Route的组件
@PermissionIndex
export default class App extends React.Component{
    render() {
        return (
            <div>
                <PermissionRouter/>
            </div>
        );
    }
}