How to convert english numbers inside a string to Persian/Arabic numbers in Objective-C?

Question

I have an english string that may or may not have numbers. But i want those numbers to be printed on screen as Persian numbers.

For example if NSString *foo =

Answer 1

Swift 3:

However other answers are correct, there is a little problem in converting String to Int.

Converting a String to Int removes left zeros which is not good (Specially in converting cell phones and national Ids). To avoid this problem I prefer replacing each English number to Persian.

static func convertToPersian(text : String)-> String {
    let numbersDictionary : Dictionary = ["0" : "۰","1" : "۱", "2" : "۲", "3" : "۳", "4" : "۴", "5" : "۵", "6" : "۶", "7" : "۷", "8" : "۸", "9" : "۹"]
    var str : String = text

    for (key,value) in numbersDictionary {
        str =  str.replacingOccurrences(of: key, with: value)
    }

    return str
}

This method can also be used to replace numbers within text and its not necessary to have a pure number to convert to Persian.