KeyNotFoundException: 给定关键字不在字典中。
StackTrace:
   在 System.ThrowHelper.ThrowKeyNotFoundException()
   在 System.Collections.Generic.Dictionary`2.get_Item(TKey key)
   在 System.Windows.SystemResources.GetDpiAwarenessCompatibleNotificationWindow(HandleRef hwnd)
   在 System.Windows.Interop.HwndHost.BuildOrReparentWindow()
   在 System.Windows.Interop.HwndHost.OnSourceChanged(Object sender, SourceChangedEventArgs 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.PresentationSource.UpdateSourceOfElement(DependencyObject doTarget, DependencyObject doAncestor, DependencyObject doOldParent)
   在 System.Windows.PresentationSource.RootChanged(Visual oldRoot, Visual newRoot)
   在 System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value)
   在 System.Windows.Window.SourceWindowHelper.ClearRootVisual()
   在 System.Windows.Window.CloseWindowFromWmClose()
   在 System.Windows.Window.WmClose()
   在 System.Windows.Window.WindowFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   在 System.Windows.Interop.HwndSource.PublicHooksFilterMessage(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)