React使用高阶组件与Hooks实现权限拦截教程详细分析

/*
 * 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/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(['edituser','checkorder'])
		//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

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './pages/App/App'
import PermissionIndex from './components/PermissionIndex/PermissionIndex'
const IndexWithPermission = PermissionIndex(App)
ReactDOM.render(
  <IndexWithPermission/>,
  document.getElementById('root')
);

import React from 'react'
function NoPermission() {
  return (
    <div>对不起，请与管理员获取权限</div>
  )
}
export default NoPermission

/*
 * 资源路径 ./src/components/PermissionHOC/PermissionHOC.js
 */
import React, { useContext } from 'react'
import PermissionContext from '../../utils/PermissionContext'
import NoPermission from '../NoPermission/NoPermission'
function PermissionHoc(authorization) {
  return function(Component){
    return function PermissionIndex(props){
      const context = useContext(PermissionContext)
      //使用useContext获取当前的权限列表，相当于类组件中的contentType静态属性
      return context.indexOf(authorization) >= 0 ? <Component {...props}></Component> : <NoPermission></NoPermission>
    }
  }
}
export default PermissionHoc

/*
 * 资源路径 ./src/components/PermissionTest/PermissionTest.js
 */
import React from 'react'
function PermissionTest(props) {
  return (
    <div>PermissionTest - {props?.name}</div>
  )
}
export default PermissionTest

/*
 * 资源路径 ./src/components/App/App.js
 */
import React, { useContext, useEffect, useRef } from 'react'
import PermissionContext from '../../utils/PermissionContext'
import PermissionHoc from '../../components/PermissionHoc/PermissionHoc'
import PermissionTest from '../../components/PermissionTest/PermissionTest'
export default function App() {
  const Edituser = PermissionHoc('edituser')(PermissionTest)
  const Edituser1 = PermissionHoc('edituser1')(PermissionTest)
  return (
    <div>
        <Edituser name="edituser"></Edituser>
        <Edituser1 name="edituser1"></Edituser1>
    </div>
  )
}