WPF Converter casting causes Visual Studio designer exception
问题 A converter such as what follows will cause the 2008 visual studio designer to not display the xaml, and error out with a "Specified cast is not valid." exception. public class ItemsVisibilityToGridColumnWidthConverter : IMultiValueConverter { public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture) { //THE TWO OFFENDING LINES... var itemsVisibility = (Visibility)values[0]; var orientation = (Orientation)values[1]; if (orientation == Orientation