- 字符串转数组
> let str = "1,2,3,11";
< undefined
> let str_arr = str.split(",")
< undefined
> str_arr
< (4) ["1", "2", "3", "11"]
- 数组增加值
> str_arr.push("1");
< 5
> str_arr
< (5) ["1", "2", "3", "11", "1"]
- 数组查找值
> str_arr.indexOf("11")
< 3
- 数组删除值
> str_arr.splice(3, 1)
< ["11"]
> str_arr
< (4) ["1", "2", "3", "1"]
- 数组转字符串
> str_arr.split(",")
< 1,2,3,1