字符串转数组:
let str ="1,2,3"
let array= str.components(separatedBy:",")
数组转字符串:
let array = ["1","2","3"]
let str = array.joined(separator:",")
let str ="1,2,3"
let array= str.components(separatedBy:",")
let array = ["1","2","3"]
let str = array.joined(separator:",")