有没有办法仅使用XAML根据Texblock自身的文本来更改Texblock前景？

<TextBlock Text="{Binding MyText}" Foreground="{Binding MyText, Converter={StaticResource TextToForegroundConverter}}" />

public class TextToForegroundConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        string text = value as string;

        // 根据文本值返回相应的前景色
        if (text == "Red")
        {
            return Brushes.Red;
        }
        else if (text == "Blue")
        {
            return Brushes.Blue;
        }
        else
        {
            return Brushes.Black;
        }
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

<Window.Resources>
    <local:TextToForegroundConverter x:Key="TextToForegroundConverter" />
</Window.Resources>