自己动手实现一个react-redux

之前试过自己动手实现一个redux，这篇blog主要记录动手实现一个react-redux的过程。

这个react-redux还有一点点小瑕疵，我以一个计数器作为例子来实现的。

这是目录结构:

这里的connect.js文件就是react-redux。

├─component│ connect.js│ counter.js│└─store index.js

index.js：

import React from "react";import ReactDom,{render} from "react-dom";import Couter from "./component/counter";import {Provider} from "./component/connect" import store from "./store/index" ReactDom.render(<Provider store={store}><Couter/></Provider>,document.getElementById("root"));

./store/index.js:

import {createStore} from "redux";function reducer(state={number:0},action) { switch (action.type){ case "add": return {number:state.number+action.count} default: return state; }}export default createStore(reducer);

./component/connect.js:

import React from "react";import PropTypes from "prop-types";//Provider是一个组件 接受一个store属性 将其内容挂载在上下文context //这样后代才可以都有办法拿到 class Provider extends React.Component{ static childContextTypes={ //设置上下文的类型是对象 store:PropTypes.object } getChildContext(){ //获取并设置后代上下文的内容 return {store:this.props.store} } render(){ return this.props.children }}let connect=(mapStateToProps,mapDispatchToProps)=>(comp)=>{ return class Proxy extends React.Component{ static contextTypes={ store:PropTypes.object } constructor(props,context){ super(props); //将参数mapStateToProps 的解构赋值 代理组件的状态 this.setState=mapStateToProps(context.store.getState()) } componentDidMount(){ this.context.store.subscribe(()=>{ this.setState(mapStateToProps(this.context.store.getState())) }) } render(){ return <comp {...this.state} {...mapDispatchToProps(this.context.store.dispatch)}/> } }}export {Provider,connect}

./component/counter.js:

import React from "react";import {connect} from "./connect";export default class Counter extends React.Component{ constructor(props){ super(props); } render(){ return ( <div> <button onClick={()=>{ this.props.add(5); }}>+</button> {this.props.n} </div> ) }}let mapStateToProps=(state)=>{ return {n:state.number}};let mapDispatchToProps=(dispatch)=>{ return { add:(count)=>{ dispatch({type:"add",count:count}) } }}export default connect(mapStateToProps,mapDispatchToProps)(Counter)

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。