using System; using System.Globalization; using Avalonia.Data.Converters; namespace ControlCatalog.Converter; public class MathSubtractConverter : IValueConverter { public object Convert(object? value, Type targetType, object? parameter, CultureInfo culture) { if (value is double dv && parameter is double dp) { return dv - dp; } return double.NaN; } public object ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture) { throw new NotSupportedException(); } }