• react-redux 的使用


    1 安装react-redux: npm install --save react-redux 

    2.之前使用redux的store.subscribe监听 store的状态改变,通过store.getState函数获取store的状态值;并且需要划分ui组件和聪明组件,着实很麻烦,引入react-redux,可以改变这一切;

    store定义如下,引入react-redux:

    import { createStore, compose, applyMiddleware } from 'redux';
    import thunk from 'redux-thunk';
    import reducer from './reducer';
    
    const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
    const store = createStore(reducer, composeEnhancers(
        applyMiddleware(thunk)
    ));
    
    export default store;

    3. 顶部组件在最外层引入store,这样所有的组件都可以使用store了;

    import React from 'react';
    import ReactDOM from 'react-dom';
    import App from './App';
    import { Provider } from 'react-redux'
    import store from './store'
    const MyApp = (
        <Provider store={store}>
            <App/>
        </Provider>
    )
    ReactDOM.render(MyApp, document.getElementById('root'));

    4.具体在组件中使用connect将 ui组件变成聪明组件:

    import React, { Component } from 'react';
    import './App.css';
    import { connect } from 'react-redux'
    import {changeInputValue,addInputValue,deleteListItem,getListData} from './store/actionCreator.js'
    class App extends Component {
      constructor(props){
        super(props);
        this.state = {}
      }
      componentDidMount(){
        this.props.getListDatas();
      }
      render() {
        const {inputValue,changeInputValue,addListItem,list,deleteList} = this.props;
        return (
          <div className="App">
            <label htmlFor="box">
              输入信息
              <input id="box" 
                value = {inputValue} 
                onChange ={changeInputValue}
              />
              <button onClick={addListItem}>提交</button>
              </label>
              <ul>
              {
                list.map((item,index) => {
                    return (
                      <li key={index} onClick={deleteList.bind(this,index) }>{item}</li>
                    )
                })
              }
              </ul>
          </div>
        );
      }
    
    }
    const mapStateToProps = (state)=> {
      return (
        {
          inputValue:state.inputValue,
          list:state.list
        }
      )
    };
    const mapDispatchToProps = (dispatch)=>{
      return {
        changeInputValue(e){
          dispatch(changeInputValue(e.target.value))
        },
        addListItem(){
          dispatch(addInputValue())
        },
        deleteList(index){
          dispatch(deleteListItem(index))
        },
        getListDatas(){
          dispatch(getListData())
        }
      }
    }
    export default connect(mapStateToProps,mapDispatchToProps)(App);
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  • 原文地址:https://www.cnblogs.com/xiaozhumaopao/p/10548370.html
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