// Yes!
            if (Request.QueryString["ID"] != null)
            {
                int EventID = 0;
                int.TryParse(Request.QueryString["ID"], out EventID);
                if (EventID > 0)
                {

                }
            }
// No..
            int eventid = 0;
            string eventidstring = Request.QueryString["ID"];
            eventid = int.Parse(eventidstring);
            if (eventid != 0)
            {

            }