InvalidCastException: 指定的转换无效。
StackTrace:
   在 System.StubHelpers.InterfaceMarshaler.ConvertToNative(Object objSrc, IntPtr itfMT, IntPtr classMT, Int32 flags)
   在 System.Management.SecuredIWbemServicesHandler.ExecQuery_(String strQueryLanguage, String strQuery, Int32 lFlags, IWbemContext pCtx, IEnumWbemClassObject& ppEnum)
   在 System.Management.ManagementObjectSearcher.Get()
   在 DynamicClass.SetBrightness(Int32 brightness)
   在 DynamicClass.<>c__DisplayClass5.<OnWindowCreated>b__3(Object sender, CancelEventArgs e)
   在 System.Windows.Window.OnClosing(CancelEventArgs e)
   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)