Add Separator "-" in text field in Swift iOS -

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• ios automatically add hyphen in text field 8 answers

i add "-" between 4 numbers when user typing in pinno text field.
example, 1234 - 5678 - 9932

// try this

func textfield(textfield: uitextfield, shouldchangecharactersinrange range: nsrange, replacementstring string: string) -> bool  {     var strtext: string? = textfield.text    if strtext == nil {      strtext = ""    }  strtext = strtext?.stringbyreplacingoccurrencesofstring("-", withstring:"")  if strtext!.characters.count > 1 && strtext!.characters.count % 4 == 0 && string != "" {     textfield.text = "\(textfield.text!)-\(string)"      return false  }   return true }