Delphi Tips

Detecting Windows Shutdown

You can use the following procedure 
to detect if Windows is shutting 
down. If your application needs to 
save data before allowing the 
shutdown to continue you can do that,
then allow Windows to shutdown 
normally.

procedure TfrmMain.WMQueryEndSession(var Message : 
                                 TWMQueryEndSession);
begin

 // Let the inherited message handler respond first
 inherited;

 if DataHasChanged then begin
    MessageBeep(MB_ICONQUESTION);
    case MessageDlg('The current Windows 
           session is ending.  Save league changes?',
           mtConfirmation, [mbYes,mbNo,mbCancel],0) of
    mrYes    : begin
                //Your data-saving code or method 
                //call goes here
                Message.Result := 1;
               end;
    mrNo     : Message.Result := 1;
    mrCancel : Message.Result := 0;
      end; {case} end
   else
      Message.Result := 1;
end;


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