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  • ES6(...)展开运算符

    函数传参
    展开运算符可以展开数组,所以不再需要apply方法,将数组转为函数的参数了

    // ES5 的写法
    function f(x, y, z) {
    // ...
    }
    var args = [0, 1, 2];
    f.apply(null, args);
    // ES6 的写法
    function f(x, y, z) {
    // ...
    }
    var args = [0, 1, 2];
    f(...args);


    数据解构
    其实就是把数组的每个数据拆开然后放进去

    let arr = ['autumn', 'wscats'];
    // 析构数组
    let y;
    [autumn, ...y] = arr;
    console.log(y) // ["wscats"]


    数据构造

    两个对象连接返回新的对象

    let x = {
    name: 'autumn'
    }
    let y = {
    age: 18
    }
    let z = {...x,...y}
    console.log(z)


    两个数组连接返回新的数组

    let x = ['autumn']
    let y = ['wscats']
    let z = [...x, ...y]
    console.log(z)// ["autumn", "wscats"]


    数组加上对象返回新的数组

    let x = [{
    name: 'autumn'
    }]
    let y = {
    name: 'wscats'
    }
    let z = [...x, y];
    console.log(z);


    数组+字符串

    let x = ['autumn'];
    let y = 'wscats';
    let z = [...x, y];
    console.log(z);

    数组+对象

    let x = {
    name: ['autumn','wscats'],
    age:18
    }
    let y = {
    ...x,//name: ['autumn','wscats'],age:18
    arr: [...x.name]//['autumn','wscats']

    }
    console.log(y)

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  • 原文地址:https://www.cnblogs.com/niwalala/p/11983229.html
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