9.扩展运算符

扩展运算符

[...]扩展运算符能将【数组】转换为逗号分隔的【参数序列】

//声明一个数组
const tfboys = ['y','w','j'];

//声明一个函数
function chunwan(){
    console.log(arguments);
}

chunwan(...tfboys);

扩展运算符应用

//1.数组的合并
const a = ['1','2'];
const b = ['3','4'];
const c = [...a,...b];
console.log(c);//['1','2','3','4']

//2.数组的克隆
const music = ['E','G','M'];
const dance = [...music];
console.log(dance);//['E','G','M']

//3.将伪数组转化为真正的数组
const divs = document.querySelectorAll('div');//object
const divArr = [...divs];
console.log(divArr);//结果为数组