• ECMA6 001 解构赋值


    传统数组赋值

    let arr = new Array();
      arr[0] = 1;
      arr[1] = 2;
      arr[2] = 3;
    console.log(arr[0],arr[1],arr[2]); //1  2  3

    每个都需要手写一次太麻烦!

    //ES6数组解构
    let [a,b,c] = [1,3,4];
    console.log(a,b,c); // 1 3 4

    ==============================================================

    //传统对象赋值
    let ob = new Object();
    ob.name = "zf";
    ob.age = 18;
    console.log(ob.name,ob.age);//  zf 18

    每个都需要手写一次太麻烦!

    //ES6对象赋值
    let {name,age} = {name:"zf",age:18};
    console.log(name,age); // zf 18
    注意 let 变量名 必须和 {对象里的属性名一致}

    let {name:n,age:a} = {name:'zf',age:[24,11]};
    console.log(n,a); // zf [24,11]
    //注意两边解构必须一致 let {} = {} 即 对象 = 对象

    ===============================================================

    //混合赋值一
    let [{name,age},[a,b],c] = [{name:'zf',age:18},[2,3],'zzz'];

    //混合赋值二
    let {name,age:[a,b]} = {name:'zf',age:[24,11]};
    console.log(name,a,b); // zf 24 11

    //混合赋值三
    let {name,age} = {name:'zf',age:[24,11]};
    console.log(name,age); // zf [24,11]

    //混合赋值四
    let [a,b] = [[2,3],{name:'zf',age:33}];
    console.log(a,b); // [2, 3] {name: "zf", age: 33}

    //混合赋值五
    let [[a,b],{name:c,age:[d,e]}] = [[2,3],{name:'zf',age:[5,7]}];
    console.log(a,b,c,d,e) //2 3 "zf" 5 7

    ================================================================

    经典案列
    let [a,b] = [1,2];
    console.log(a,b);//1,2
    [a,b] = [b,a];
    console.log(a,b);//2,1

    //传统写法 ============================================
    let a = 1;
    let b = 2;
    console.log(a,b);//1,2
    let c;
    c=a;
    a=b;
    b=c;
    console.log(a,b);//2,1

    tips解构赋值
    1、两边数据解构格式必须一致
    2、声明和赋值 一句话里完成
    3、右边不能为空!否则会会报错

  • 相关阅读:
    GNU make manual 翻译( 一百五十八)
    GNU make manual 翻译( 一百五十六)
    GNU make manual 翻译( 一百五十九)
    GNU make manual 翻译( 一百六十二)
    2007高考作文题目
    美国电视节目网上免费收看指南 JOOST
    临时算法文件
    Delaunay三角网生成算法(转)
    警示箴言
    PC平台下海量地形的分页调度和实时渲染(转)
  • 原文地址:https://www.cnblogs.com/anduyinglufei/p/10352729.html
Copyright © 2020-2023  润新知