counter.reducer => index =>counter

index.js

import React from‘react’; import ReactDOM from‘react-dom’; import App from ‘./App’ import { createStore } from ‘redux’ import CounterReducerfrom ‘./Store/Reducer/Counter.reducer’ import { Provider } from ‘react-redux’ const store = createStore(CounterReducer) ReactDOM.render( <React.StrictMode> <Provider store={store}><App/></Provider> </React.StrictMode>, document.getElementById(‘root’) );

counter.js

import React, { Component } from ‘react’ import { connect } from ‘react-redux’ function Counter(props) { console.log(props) return ( <div> <button>+1</button> <span>{props.count}</span> <button>-1</button> </div> ) } const mapStateToProps = state => ({ count:state.count }) //connect方法指定传什么数据以及传给谁 export default connect(mapStateToProps)(Counter)