var arr = [1,2,3]
//转字符串
var str = arr.join(",") ===> "1,2,3"
//或者 arr.join(" * ") ===> "1*2*3"
转数组
str.split(",") === > ['1', '2', '3']
var arr = [1,2,3]
//转字符串
var str = arr.join(",") ===> "1,2,3"
//或者 arr.join(" * ") ===> "1*2*3"
转数组
str.split(",") === > ['1', '2', '3']