classAppextendsReact.Component{
    state={
        name:'jack',
        age:19,
        gender:'男',
        count:1
    }
    render() {
        return
            御剑乘风来,除魔天地间!
            
        

  const Child = (props) => {
    console.log(props,99);
    return

      御剑乘风来,除魔天地间!===Child======{props.count}
    
    };

classAppextendsReact.Component{
    state={
        name:'jack',
        age:19,
        gender:'男',
        count:1
    }
  handle2=(msg)=>{
        console.log(msg,77); //  123
    }
    render() {
        return
            御剑乘风来,除魔天地间!==
            
        

子组件：

  const Child = (props) => {
    console.log(props,99);
    var handle=()=>{
            console.log(111);
      props.getMsg('123')
        }
    return

      御剑乘风来,除魔天地间!===Child======
        child1
    };

3、非父子传值

child1 向 child2 传值

思路：child  传到app  ,然后app传到child2

classAppextendsReact.Component{
    state={
        name:'jack',
        age:19,
        gender:'男',
        count:1
    }
  handle2=(msg)=>{
        console.log(msg,77); //  123this.setState({
      count:this.state.count+msg
    })
    }
    render() {
        return
            御剑乘风来,除魔天地间!==
            
        
        
    }

子组件1：

const Child = (props) => {
    console.log(props,99);
    var handle=()=>{
            console.log(111);
      props.getMsg('123')
        }
    return

      御剑乘风来,除魔天地间!===Child======
        child1
    };
  const Child2 = (props) => {
    console.log(props,99);
    var handle=()=>{
            console.log(111);
      props.getMsg('123')
        }
    return

      御剑乘风来,除魔天地间!===Child======
        child1
    };

4、Context 方法 传值 【类似vue的 provide / inject】

步骤：

1- const  {Provider,Consumer} = React.createContext()
2- Provider包裹父组件 定义value是需要传的值  ====
3- Consumer包裹需要接收数据的组件 data接收数据

            {data=>(
                    

                        御剑乘风来,除魔天地间! ==Child2*****{data}                
                    
            )}

代码如下：

import React from 'react'const  {Provider,Consumer} = React.createContext()
const Child = (props) => {
    console.log(props,99);
    return 

        御剑乘风来,除魔天地间!===Child

}; 
classChild2extendsReact.Component{
    render() {
        return 

                
            {data=>(
                    

                        御剑乘风来,除魔天地间! ==Child2*****{data}                
                    
            )}
            
        
    }
} 
classAppextendsReact.Component{
    state={
        name:'jack',
        age:19,
        gender:'男',
        count:1
    }
    render() {
        return 
            御剑乘风来,除魔天地间!=={this.state.name}
            
            
        
    }
}
export default App