namespace Account.UI.Converters { public class CardNumberObfuscatorConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, CultureInfo culture) { var cardNumber = value as string; var numberSet = cardNumber.Split(' '); var last4Digits = numberSet[numberSet.Length - 1]; return $"XXXX XXXX XXXX {last4Digits}"; } public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) { throw new NotImplementedException(); } } }