Win32Exception: 句柄无效。
--NativeErrorCode: 6
StackTrace:
   在 Standard.NativeMethods.SetWindowRgn(IntPtr hWnd, IntPtr hRgn, Boolean bRedraw)
   在 System.Windows.Shell.WindowChromeWorker._SetRoundingRegion(Nullable`1 wp)
   在 System.Windows.Shell.WindowChromeWorker._HandleWindowPosChanged(WM uMsg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   在 System.Windows.Shell.WindowChromeWorker._WndProc(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)