react的state和setState
react的状态组件
react的有state的为状态组件,创建形式为:
import React, { Component } from "react"; import './index.css' //有状态的组件 即有state //jsx语句 class Box extends Component { state={ num:1, open: false, } add=()=>{ console.log(this); this.setState({ num:this.state.num+1 }); this.setState({ open: !this.state.open }) } reduce(){ this.setState({ num: this.state.num-1 }) } render() { let open=this.state.open, className=open?'index':'unindex'; return () } } export default Box;我在持续增加哦:{this.state.num}
{this.reduce()}}>点击我可以减少
无状态组件创建形式为:
import './App.css'; import Box from './index/index'; function App() { return ("App" id="app">); } export default App;"App-header"> Edit
src/App.js
and save to reload.<a className="App-link" href="https://reactjs.org" target="_blank" rel="noopener noreferrer" > Learn React
即函数和class、component的区别。