C # winform close button

Previously, C # was used as the web, and C # was not used as the winform. In the past few days, a household financial management system was created, and the system still had certain availability, however, when processing the close button that comes with the form window, whether I use the close () method or the Resource Recycling method, the ghost cannot be closed, the result is closed using this method. Similar to closing a thread, it should be good. Wow Haha ~

 1     ///     <Summary>  
  2     ///  Closed button in the Main Window
  3     ///    </Summary>  
  4     ///     <Param name = "sender"> </param>  
  5     ///     <Param name = "E"> </param>  
  6       Private     Void  Mainform_formclosing (  Object  Sender, formclosingeventargs E)
  7   {
  8   Dialogresult result;
  9   Result  =  MessageBox. Show (  " Are you sure you want to exit?  "  ,  "  Exit  "  , Messageboxbuttons. okcancel, messageboxicon. Question );
  10     If  (Result  =  Dialogresult. OK)
  11   {
  12  Application. exitthread ();
  13   }
  14     Else  
  15   {
  16   E. Cancel  =     True  ;
  17  }
  18   } 

The formclosing event of form is added here, but it cannot be done before... Sorry, it is probably because it is too different. Haha record it.