JS iterator进行遍历Map Set

   'use strict'
        //遍历数组元素
        var arr = [3,4,5]
        for (var arrKey of arr) {
            console.log(arrKey)
        }
        //遍历map
        var map = new Map([["张三",20],["李四",28],["王五",35]])
        for (let x of map) {
            console.log(x)
        }
        //遍历set
        var set = new Set([5,6,7])
        for (let x of set) {
            console.log(x)

运行结果：