我想在 xaml 中设置类型“类型”的依赖属性。这可以正常工作,但是当我以隐式或显式样式设置此值时,将引发异常(未处理的异常)。
我创建了一个空的 Silverlight 应用程序并添加了一个用户控件 (DataFormControl)。这是此控件背后的代码:
public DataFormControl()
{
InitializeComponent();
}
public static readonly DependencyProperty TitleProperty = DependencyProperty.Register("Title", typeof(string), typeof(DataFormControl), null);
public string Title
{
get { return (string)GetValue(TitleProperty); }
set { SetValue(TitleProperty, value); }
}
public static readonly DependencyProperty TypeToReflectProperty = DependencyProperty.Register("TypeToReflect", typeof(Type), typeof(DataFormControl), null);
public Type TypeToReflect
{
get { return (Type)GetValue(TypeToReflectProperty); }
set { SetValue(TypeToReflectProperty, value); }
}
public string GetCombo()
{
string returnValue = (Title ?? "no title") + " ; " + (TypeToReflect != null ? TypeToReflect.Name : "unkown Type");
return returnValue;
}
private void Refresh_Button(object sender, RoutedEventArgs e)
{
this.ResultBox.Text = GetCombo();
}
这里是 XAML 代码:
<Grid x:Name="LayoutRoot">
<StackPanel Orientation="Horizontal">
<Button Click="Refresh_Button">Refresh</Button>
<TextBlock x:Name="ResultBox" />
</StackPanel>
</Grid>
现在问题出现在引用 this 并使用全局样式的控件中:
<StackPanel>
<StackPanel.Resources>
<Style TargetType="local:DataFormControl">
<Setter Property="Title" Value="Implicit Name" />
<Setter Property="TypeToReflect" Value="local:DataFormControl" />
</Style>
</StackPanel.Resources>
<TextBlock FontWeight="Bold">Test App</TextBlock>
<local:DataFormControl Title="123" />
<local:DataFormControl Title="Kuh" />
<local:DataFormControl TypeToReflect="local:DataFormControl" />
<local:DataFormControl />
</StackPanel>
如果我删除“TypeToReflect”-Setter,那么一切正常。title 属性的全局样式也可以正常工作。
这是一个错误还是有解决方法?
我需要这种类型,因为我想对它使用反射。
编辑:
异常信息:
Message is always. [Line: 0 Position: 0]
ExceptionType: Unhandled Exception
ExceptionObject: XamlParseException
堆栈跟踪:
at MS.Internal.XcpImports.CheckHResult(UInt32 hr)
at MS.Internal.XcpImports.ConvertStringToTypedCValue(IntPtr pContext, UInt32 cClrTypeName, String clrTypeName, UInt32 cValue, String value, CValue& outVal, Int32& typeIndex)
at MS.Internal.SilverlightTypeConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value)
at MS.Internal.XcpImports.GetManagedPropertyValueFromStyle(Boolean useBuiltInStyle, IManagedPeerBase obj, DependencyProperty property, Object& value)
at System.Windows.FrameworkElement.GetValueFromStyle(DependencyProperty property, Object& value)
at System.Windows.DependencyObject.EvaluateBaseValue(DependencyProperty property, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, ValueOperation operation)
at System.Windows.DependencyObject.EvaluateEffectiveValue(DependencyProperty property, EffectiveValueEntry oldEntry, EffectiveValueEntry newEntry, ValueOperation operation)
at System.Windows.DependencyObject.UpdateEffectiveValue(DependencyProperty property, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, ValueOperation operation)
at System.Windows.DependencyObject.InvalidateProperty(DependencyProperty property)
at MS.Internal.FrameworkCallbacks.InvalidateProperty(IntPtr nativeTarget, UInt32 propertyId)
内部异常为空。