private void DeleteSubject()
        {
            var win = GetSelectedSubject();

            if (win == null || win.SubjectID > 0)
            {
                Message(MessageTypes.Error, "Please Select to delete Staff Detail");
                return;
            }
            if (!DeleteMessage())
            {
                return;
            }

            SubjectRepo.Remove(win.SubjectID);
            RefreshList();
        }