public Counter(TextBox InputTextbox, Label CounterLabel)
    {
        int NB;
        var tempText = InputTextbox.Text;

        NB = (InputTextbox.MaxLength - tempText.Length);
        CounterNumber counterNumber = new CounterNumber {
            Number = NB.ToString()
        };

        CounterLabel.Content = counterNumber;
        if (NB == 0)
        {
            CounterLabel.Foreground = new SolidColorBrush(Colors.Red);
        }
    }