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react-redux?action傳參及多個state處理的實現_React

作者：敢問 ? 更新時間： 2022-09-20 編程語言

action 中傳遞參數

App.js 中傳遞自己的參數

function App (props){
  console.log(props,'===')
  return (
    <div>
      <h1>redux</h1>
      <button onClick={()=>{props.increment(10)}}>增加</button>
      <p>{props.count}</p>
      <button onClick={()=>{props.decrement(3)}}>減少</button>
    </div>
  )
}

action.js 傳參

export  const increment = (num) => ({ type:'increment',payload:num })
export  const decrement = (num) => ({ type:'decrement',payload:num })

reduce.js 中打印 action

import { initstate } from "../state/state";
  //2.定義 reducer  第一個參數  state  第二個參數 action
 export  function reducer(state = initstate,action){
    console.log(action,'===action')
    switch(action.type){
      case 'increment' :return {count:state.count + action.payload}
      break;
      case 'decrement' :return {count:state.count - action.payload}
      break;
      default :return state
    }
  }

多個state狀態

增加一個新的state。控制div 的背景顏色

定義color 組建

function Color (props){
    let style = {
        width:100,
        height:100,
        background:props.color,
        textAlign:'center',
        lineHeight:100,
    }
    console.log('colorprops',props)
    return(
        <div>
            <button onClick={()=>{props.fngreen()}}>green</button>
            <button onClick={()=>{props.fnred()}}>red</button>
            <div style={style}>多個 state</div>
        </div>
    )
}
export default Color

定義state

// 3.定義state
export const  initstate = {
    count:0
}
//color
export const  colorstate = {
    color:'red'
}

定義action

export  const increment = (num) => ({ type:'increment',payload:num })
export  const decrement = (num) => ({ type:'decrement',payload:num })
//處理color
export  const fngreen = () => ({ type:'fngreen'})
export  const fnred = () => ({ type:'fnred' })

定義reducer 處理color的reducer1

import { colorstate } from "../state/state";
  //2.定義 reducer  第一個參數  state  第二個參數 action
 export  function reducer(state = colorstate,action){
    console.log(action,'===color')
    switch(action.type){
      case 'fngreen' :return {color:'green' }
      break;
      case 'fnred' :return {color:'red'}
      break;
      default :return state
    }
  }

store/index? ? 創建store

import {createStore} from 'redux'
import{ reducer } from './reducer/reducer1'
  //1. 定義store
  let store = createStore( reducer )
  export default store 
  console.log(store)

color組建

import { connect } from 'react-redux';
import { bindActionCreators } from 'redux'
import *as actionobj from '../store/action/action'
function Color (props){
    let style = {
        width:100,
        height:100,
        background:props.color,
        textAlign:'center',
        lineHeight:100,
    }
    console.log('colorprops',props)
    return(
        <div>
            <button onClick={()=>{props.fngreen()}}>green</button>
            <button onClick={()=>{props.fnred()}}>red</button>
            <div style={style}>多個 state</div>
        </div>
    )
}
const mapStateToProps = function(state){
    return {color:state.color}
}
    const mapDispatchToProps = (dispatch) => {
    return bindActionCreators(actionobj,dispatch)
}
export default connect(mapStateToProps,mapDispatchToProps)(Color);

?整合 reducer? ??combineReducers(reducers)

redux/combineReducers.md at master · reduxjs/redux · GitHub

多個reducer進行整合? ?reducer下創建index.js

?reducer/index.js

import { combineReducers } from 'redux'
import reducer1 from './reducer1'
import reducer2 from './reducer2'
export default combineReducers({
    reducer1,
    reducer2
})

reducer1.js

import { colorstate } from "../state/state";
//2.定義 reducer  第一個參數  state  第二個參數 action
export default function reducer1(state = colorstate,action){
    console.log(action,'===color')
    switch(action.type){
      case 'fngreen' :
          return {color:'green' }  
      break;
      case 'fnred' :
          return {color:'red'}  
      break;
      default :return state
    }
}

reducer2.js

import { initstate } from "../state/state";
  //2.定義 reducer  第一個參數  state  第二個參數 action
 export default  function reducer2(state = initstate,action){
    console.log(action,'===action')
    switch(action.type){
      case 'increment' :return {count:state.count + action.payload}
      break;
      case 'decrement' :return {count:state.count - action.payload}
      break;
      default :return state
    }
  }

store/index.js

import {createStore} from 'redux'
import reducer  from './reducer'
//1. 定義store
let store = createStore( reducer )
export default store

App.js?

注意：combineReducers?? 返回的結果是一個對象

{
    reducer1:{color:'red'},
    reducer2:{count:0}
}

所以在使用的。候需要。{props.reducer2.count}? ?background:props.reducer1.color,?

映射的時候需要解構

reducer1.js. 和reducer2.js? 解構state

import { colorstate } from "../state/state";
//2.定義 reducer  第一個參數  state  第二個參數 action
export default function reducer1(state = colorstate,action){
    console.log(action,'===color')
    switch(action.type){
      case 'fngreen' :
          return {...state,color:'green' }  
      break;
      case 'fnred' :
          return {...state,color:'red'}  
      break;
      default :return state
    }
}

import { initstate } from "../state/state";
  //2.定義 reducer  第一個參數  state  第二個參數 action
 export default  function reducer2(state = initstate,action){
    console.log(action,'===action')
    switch(action.type){
      case 'increment' :return {...state,count:state.count + action.payload}
      break;
      case 'decrement' :return {...state,count:state.count - action.payload}
      break;
      default :return state
    }
  }

原文鏈接：https://blog.csdn.net/weixin_41040445/article/details/125906957

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網站首頁編程語言正文

react-redux?action傳參及多個state處理的實現_React

目錄

action 中傳遞參數

多個state狀態

相關推薦

日本免费高清视频-国产福利视频导航-黄色在线播放国产-天天操天天操天天操天天操|www.shdianci.com

網站首頁 編程語言 正文

react-redux?action傳參及多個state處理的實現_React

目錄

action 中傳遞參數

多個state狀態

相關推薦

網站首頁編程語言正文