1. 把数组对象转换为Set对象
var arr = [1,2,3,4,5,6,7,6,6,7];
console.log(arr);
var s = new Set(arr);
console.log(s);
2. 把Set对象转为数组
var s = new Set([1,2,3,4]);
console.log(s);
var arr2 = [...s];
console.log(arr2);
原文：https://www.cnblogs.com/zhangruiqi/p/9003947.html