标签:move alt lis add back sed == 加载 综合案例
1、工具类storage.js
var app ={ set(key,value){ localStorage.setItem(key,JSON.stringify(value)); }, get(key){ return JSON.parse(localStorage.getItem(key)); }, delete(key){ localStorage.removeItem(key); }, countFalseNum(key){ let count=new Number(0); let list = JSON.parse(localStorage.getItem(key)); list.map(function (value,key) { if(value.checked==false){ count = count+1; } }) return count; }, countTrueNum(key){ let count=new Number(0); let list = JSON.parse(localStorage.getItem(key)); list.map(function (value,key) { if(value.checked==false){ count = count+1; } }) return count; } } export default app;
2、todolist案例实现
import React from ‘react‘; import storage from ‘../modules/storage‘; class Todolist1 extends React.Component{ constructor(props){ super(props); this.state={ list:[], finishList:[ /* { title:"录制java", checked:true }, { title:"录制react", checked:false }, { title:"录制python", checked:true }*/ ] }; } //生命周期函数 页面加载就会触发 componentDidMount(){ //获取缓存的数据 let todoList = storage.get("TodoList"); if(todoList){ this.setState({ finishList:todoList }) } } addData=(e)=>{ if(e.keyCode==13){ let title=this.refs.title.value; let tempList = this.state.finishList; tempList.push({ title:title, checked:false }) this.setState({ list:tempList }); //增加框设置为空 this.refs.title.value=""; //缓存数据,使用localStorage,而将一个对象转为字符串使用JSON.stringify()函数 storage.set("TodoList",tempList); } } changeState=(key)=>{ let templist =this.state.finishList; templist[key].checked =!templist[key].checked; this.setState({ list:templist }); storage.set("TodoList",templist); } deleteData=(key)=>{ let templist =this.state.finishList; templist.splice(key,1); this.setState({ list:templist }) storage.set("TodoList",templist); } render(){ return ( <div> Todolist index <h2>Todolist演示</h2> <input ref="title" onKeyUp={this.addData}/> <hr/> <h2> </h2> <h2>正在进行</h2> <hr/> { this.state.finishList.map( (value,key)=> { if(value.checked==false){ return( <li key={key}> <input type="checkbox" checked={value.checked} onChange={this.changeState.bind(this,key)}/>{value.title} ---<button onClick={this.deleteData.bind(this,key)}>删除</button> </li> ) } }) } <h2>已完成事项</h2> { this.state.finishList.map( (value,key)=> { if(value.checked==true){ return( <li key={key}> <input type="checkbox" checked={value.checked} onChange={this.changeState.bind(this,key)} />{value.title} ---<button onClick={this.deleteData.bind(this,key)}>删除</button> </li> ) } }) } <hr/> </div> ) } } export default Todolist1;
3、app.js加载该组建
import React, { Component } from ‘react‘; import ‘./assets/css/App.css‘; import Todolist1 from ‘./components/Todolist1‘; class App extends Component { render() { return( <div> 你好 <Todolist1/> </div> ) } } export default App;
注意:
1、localStorage的使用 2、this对象的指向
react综合案例-todolist、localstorage缓存数据
标签:move alt lis add back sed == 加载 综合案例
原文地址:https://www.cnblogs.com/ywjfx/p/10421272.html