• ... 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 = ['易洋千玺','王源','王俊凯'];
//声明一个函数
function chunwan(){
	console.log(arguments);
}
chunwan(...tfboys); //等价于chunwan('易洋千玺','王源','王俊凯')

• 与rest参数的区别

1. 应用场景

• 数组的合并

const kuaizi = ['王太利','唐探'];
const fenghuang = ['玲花','曾毅'];
//ES5 写法
const hebing1 = kuaizi.concat(fenghuang);
//ES6 使用扩展运算符
const hebing2 = [...kuaizi,...fenghuang];

• 数组的克隆

const sanzhihua = ['E','G','M'];
const sanyecao = [...sanzhihua]; //浅拷贝，等价于['E','G','M']

• 场景3: 将伪数组转为真正的数组

const divs = document.querySelectorAll("div");
const divArr = [...divs];