轉換器無法轉換錯誤

我在我的silverlight項目中有BooleanToVisibilityConverter和InverseBooleanToVisibilityConverter。這兩個都相當標準，但由於某種原因，在這一個對話框中，他們拋出了很多錯誤（至少我認爲它的轉換器）。我似乎無法得到它拋出任何異常我可以查看我只是得到這個輸出，我不知道爲什麼！轉換器無法轉換錯誤

System.Windows.Data Error: 'MS.Internal.Data.DynamicValueConverter' converter failed to convert value 'True' (type 'System.String'); BindingExpression: Path='CategoryTitle' DataItem='null' (HashCode=0); target element is 'System.Windows.Controls.Grid' (Name=''); target property is 'Visibility' (type 'System.Windows.Visibility').. System.ArgumentException: Requested value 'True' was not found. 
    at System.Enum.EnumResult.SetFailure(ParseFailureKind failure, String failureMessageID, Object failureMessageFormatArgument) 
    at System.Enum.TryParseEnum(Type enumType, String value, Boolean ignoreCase, EnumResult& parseResult) 
    at System.Enum.Parse(Type enumType, String value, Boolean ignoreCase) 
    at MS.Internal.SilverlightTypeConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value) 
    at MS.Internal.Data.DefaultValueConverter.ConvertHelper(Object o, Type destinationType, CultureInfo culture, Boolean isForward) 
    at MS.Internal.Data.TargetDefaultValueConverter.Convert(Object o, Type type, Object parameter, CultureInfo culture) 
    at MS.Internal.Data.DynamicValueConverter.Convert(Object value, Type targetType, Object parameter, CultureInfo culture) 
    at System.Windows.Data.BindingExpression.ConvertValue(Object value, DependencyProperty dp, String failureResource).

這裏是XAML

<converters:InverseBooleanToVisibilityConverter x:Key="InverseBoolToVisibility" /> 
<Grid Visibility="{Binding CategoryTitle, Converter={StaticResource InverseBoolToVisibility}, FallbackValue=True}">

酒店林勢必：

public bool CategoryTitle { get; set; }

和轉換器本身

public class InverseBooleanToVisibilityConverter : IValueConverter 
{ 
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     return !(bool)value ? Visibility.Visible : Visibility.Collapsed; 
    } 

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     Visibility vis = (Visibility)value; 

     if (vis != Visibility.Visible) 
     { 
      return true; 
     } 

     return false; 
    } 
}

來源

2013-11-04 Chris

System.ArgumentException: Requested value 'True' was not found.

這是因爲Visibility需要Visibility Enum類型。您正試圖在您的FallBackValue中爲此使用bool值。

來源

2013-11-04 14:25:20 gleng

轉換器無法轉換錯誤

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