React Hooks一.简单对比:1.先来对比一下原始写法2.Hooks写法二.useState具体使用三.useEf

一.简单对比:

1.先来对比一下原始写法

2.Hooks写法

二.useState具体使用

import React, { useState } from 'react'


const Index = () => {
    const [count, setCount] = useState(0) //数组结构
    const [age, setAge] = useState(18) //数组结构
    //..? let _useState = useState(0)
    // let count = _useState[0]
    // let setState = _useState[1]
   
   // useState 必须按照顺序渲染,不允许存在于条件判断声明中

    return (
        <div>
            <p>幅度{count}</p>  
            <button onClick={()=>{setCount(count+1)}}>添加</button>
            <p>年龄{age}</p>  
            <button onClick={()=>{setAge(age+count)}}>添加</button>
        </div>
    );
}

export default Index;