var str="abcdefg"
//1、将字符串转成数组形式：split()
var arr=str.split("")
console.log(arr)//["a", "b", "c", "d", "e", "f", "g"]
//2、将数组转成字符串形式：join()
var strings=arr.join("")//
console.log(strings)//abcdefg
//3、将数组元素反转：reverse()函数只能反转数组
var rever=arr.reverse()
console.log(rever.join(""))//gfedcba
原文：https://www.cnblogs.com/lyt0207/p/12397708.html