OutOfMemoryException
   在 System.Windows.Automation.Provider.AutomationInteropProvider.RaiseAutomationEvent(AutomationEvent eventId, IRawElementProviderSimple provider, AutomationEventArgs e)
   在 System.Windows.Automation.Peers.AutomationPeer.RaiseAutomationEvent(AutomationEvents eventId)
   在 System.Windows.Automation.Peers.AutomationPeer.RaiseFocusChangedEventHelper(IInputElement newFocus)
   在 System.Windows.Input.KeyboardDevice.ChangeFocus(DependencyObject focus, Int32 timestamp)
   在 System.Windows.Input.KeyboardDevice.TryChangeFocus(DependencyObject newFocus, IKeyboardInputProvider keyboardInputProvider, Boolean askOld, Boolean askNew, Boolean forceToNullIfFailed)
   在 System.Windows.Input.KeyboardDevice.Focus(DependencyObject focus, Boolean askOld, Boolean askNew, Boolean forceToNullIfFailed)
   在 System.Windows.Input.KeyboardDevice.Focus(IInputElement element)
   在 System.Windows.Interop.HwndKeyboardInputProvider.OnSetFocus(IntPtr hwnd)
   在 System.Windows.Interop.HwndKeyboardInputProvider.FilterMessage(IntPtr hwnd, WindowMessage message, 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)