如何检查字符串是否仅包含 Swift 中允许的字符

Question

I've searched a way to check in Swift if a string contains particular characters and just them. For exemple, if a string contains them but it contains other characters as well, it should return false .

What I need is something which allows me to say if a string contains JUST some elements. For exemple: If I wanna know if "101010010101" contains ONLY 1 and 0 it should return true . But "1901919117" doesn't contains ONLY 1 and 0 it should return false .

Answer 1

Maybe You could go with something like this (just check if Your allowed characters are super set of Your string):

import Foundation

let allowedChars = Set("10")

print(allowedChars)

let a = "101010010101"
let b = "1901919117"

print(allowedChars.isSuperset(of: a)) //prints true

print(allowedChars.isSuperset(of: b)) //prints false