ArgumentException: 指定的 Visual 已经是另一个 Visual 的子级或者已经是 CompositionTarget 的根。 --Message: 指定的 Visual 已经是另一个 Visual 的子级或者已经是 CompositionTarget 的根。 StackTrace: 在 System.Windows.Media.VisualCollection.Insert(Int32 index, Visual visual) 在 System.Windows.Controls.UIElementCollection.InsertInternal(Int32 index, UIElement element) 在 DynamicClass.aa.<>c__DisplayClass148.<OnWindowLoaded>b__de(Object s, SelectionChangedEventArgs e) 在 System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) 在 System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) 在 System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) 在 System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) 在 System.Windows.Controls.DataGrid.OnSelectionChanged(SelectionChangedEventArgs e) 在 System.Windows.Controls.Primitives.Selector.SelectionChanger.End() 在 System.Windows.Controls.Primitives.Selector.SelectionChanger.SelectJustThisItem(ItemInfo info, Boolean assumeInItemsCollection) 在 System.Windows.Controls.Primitives.Selector.OnSelectedItemChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) 在 System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e) 在 System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e) 在 System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args) 在 System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType) 在 System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal) 在 System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value) 在 DynamicClass.aa.<>c__DisplayClass148.<OnWindowLoaded>b__df(Object s, MouseEventArgs e) 在 System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) 在 System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) 在 System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) 在 System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction) 在 System.Windows.ReverseInheritProperty.OnOriginValueChanged(DependencyObject oldOrigin, DependencyObject newOrigin, IList`1 otherOrigins, DeferredElementTreeState& oldTreeState, Action`2 originChangedAction) 在 System.Windows.Input.MouseDevice.ChangeMouseOver(IInputElement mouseOver, Int32 timestamp) 在 System.Windows.Input.MouseDevice.PreNotifyInput(Object sender, NotifyInputEventArgs e) 在 System.Windows.Input.InputManager.ProcessStagingArea() 在 System.Windows.Input.InputManager.ProcessInput(InputEventArgs input) 在 System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport) 在 System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel) 在 System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled) 在 System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) 在 MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) 在 MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) 在 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) 在 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)