// ParentComponent.js
import React, { useState } from 'react';
import ChildComponent from './ChildComponent';
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function ParentComponent() {
  const [messageFromChild, setMessageFromChild] = useState('');
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  const handleMessageFromChild = (message) => {
    setMessageFromChild(message);
  };
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  return (
    <div>
      <h1>Parent Component</h1>
      <p>Message from Child: {messageFromChild}</p>
      <ChildComponent giveChildren={parentData} onMessage={handleMessageFromChild} />
    </div>
  );
}
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export default ParentComponent;

// ChildComponent.js
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//1.函數(shù)式組件
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import React from 'react';
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function ChildComponent(props) {
  const { onMessage , parentData } = props;
  const sendMessageToParent = () => {
    onMessage('Hello from Child!');
  };
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  return (
    <div>
      <h2>Child Component</h2>
      <h2>{ parentData }</h2>
      <button onClick={sendMessageToParent}>Send Message to Parent</button>
    </div>
  );
}
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export default ChildComponent;
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//1. 類組件
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import React, { Component } from 'react'
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export default class ChildComponent extends Component {
    render() {
        return (
            <div>
                {this.props.parentToChild}
            </div>
        )
    }
}

//跨組件通信
import React, { Component } from 'react'
//創(chuàng)建context 給初始值
const UserMessage = React.createContext({
    nickName: 'yyy',
    level: 1
})
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export default class TextSingal extends Component {
    constructor(props) {
        super(props)
        this.state = {
            nickName: 'kkk',
            level: 99,
            name: 'ppp',
            age: 9999
        }
    }
    render() {
        const { name, age } = this.state
        return (
            <div>
                <h2>爺爺組件</h2>
                <h3>name:{name}</h3>
                <h3>age:{age}</h3>
                {/* 改變數(shù)據(jù)孫組件也更新 */}
                <button onClick={() => this.handelClick()}>updated</button>
                {/* 傳入state對(duì)象和foo回調(diào)函數(shù) */}
                {/* foo函數(shù)用于孫組件和爺組件通信 */}
                <UserMessage.Provider value={{ ...this.state, foo: (name, age) => this.updateDatas(name, age) }}>
                    <Father />
                </UserMessage.Provider>
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            </div>
        )
    }
    handelClick() {
        this.setState({
            nickName: '虎威神',
            level: 9999
        })
    }
    updateDatas(name, age) {
        this.setState({
            name,
            age
        })
    }
}
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class Father extends Component {
    render() {
        return (
            <div>
                <h2>爸爸組件</h2>
                <Son />
            </div>
        )
    }
}
class Son extends Component {
    render() {
        // 解構(gòu)
        const { nickName, level, foo } = this.context
        return (
            <div>
                <h2>兒子組件</h2>
                <h3>nickname:{nickName}</h3>
                <h3>level:{level}</h3>
                {/* 下面兩種調(diào)用方式都可以 */}
                {/* 改變爺組件的數(shù)據(jù) */}
                <button onClick={() => this.handelClick()}>updated</button>
                <button onClick={() => foo('牛霸天', 18)}>updated</button>
            </div>
        )
    }
    handelClick() {
        this.context.foo('牛霸天', 18)
    }
}
// 接受爺組件傳遞的值
Son.contextType = UserMessage

//父組件
import React, {Component} from "react"
import Abrother from './Abrother'
import Bbrother from './Bbrother'
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export default class common extends Component {
    // 公共的組件部分
    state = {
        inputValue:''
    }
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    handleUpdate = (inputValue) => {
        this.setState({
            inputValue
        })
    }
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    render(){
        return(
            <>
              <Abrother sendFn={this.handleUpdate}/>
              <Bbrother sendValue={this.state.inputValue}/>
            </>
        )
    }
}

import React,{Component} from "react";
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export default class Abrother extends Component {
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    // 兄弟組件A需要將值先傳給一個(gè)公共的父組件
    state = {
        inputValue:''
    }
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    handleChange = (e)=>{
        console.log(e.target.value);
        this.setState({
            inputValue:e.target.value
        })
    }
    handleSend = () => {
        const {sendFn} = this.props;
        sendFn(this.state.inputValue)
    }
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    render(){
        return(
            <>
               <div>
                   <span>A組件</span>
                   <input type='text' value={this.state.inputValue} onChange={this.handleChange}></input>
                   <button onClick={this.handleSend}>發(fā)送A組件的值</button>
               </div>
            </>
        )
    }
}

import React, {Component} from "react"
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export default class Bbrother  extends Component {
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    render(){
        const { sendValue} = this.props;
        return (
            <div>
                <span>b組件</span>
                <h1>{ sendValue }</h1>
            </div>
        )
    }
}