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    纸飞机博客:对象和数组的解构赋值

    作者:[db:作者] 时间:2021-09-07 10:08

    按照一定模式,从数组和对象中提取值, 对变量进行赋值。这被称为解构。通俗讲就是怎么快速地从对象和数组中获取到你想要的数据。

    解构对象

    基本

    let {name,age} = {name:"swr",age:28};
    console.log(name) //'swr'
    console.log(age) //28

    使用不同名称

    let {name:Name,age} = {name:'swr',age:28}
    console.log(Name) // 'swr'
    console.log(age) //28

    嵌套解构

    let person = {
        address: {
            province:'广东',
            city:'深圳'
        }
    }
    let {address: {province}} = person;
    console.log(province) //广东

    解构数组

    基本

    let [a, b, c] = [1,2,3];
    console.log(a) //1
    console.log(b) //2

    嵌套

    let [a,[b, c]] = [1, [2,3]];
    console.log(b) //2
    console.log(c) //3

    可忽略

    let [a,,b] = [1,2,3];
    console.log(a) //1
    console.log(b) //3

    剩余运算

    let [a,...b] = [1,2,3];
    console.log(a) //1
    console.log(b) //[2,3]

    结合数组解构和对象解构

    let obj = {
        num: [1,2],
        …
    }
    let {num: [firstnum, secondnum]} = obj;
    console.log(firstnum, secondnum); //1,2
    cs
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