Formatting a UITextField for credit card input like (xxxx xxxx xxxx xxxx)

Question

I want to format a UITextField for entering a credit card number into such that it only allows digits to be entered and automatically inserts spaces so that the

Answer 1

Swift 3.2

Little correction in the @Lucas answer and working code in swift 3.2. Also removing the space character automatically.

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

    if range.location == 19 {
        return false
    }

    if range.length == 1 {
        if (range.location == 5 || range.location == 10 || range.location == 15) {
            let text = textField.text ?? ""
            textField.text = text.substring(to: text.index(before: text.endIndex))
        }
        return true
    }

    if (range.location == 4 || range.location == 9 || range.location == 14) {
        textField.text = String(format: "%@ ", textField.text ?? "")
    }

    return true
}