protected void Application_BeginRequest(Object sender, EventArgs e)        {            string url = Request.AppRelativeCurrentExecutionFilePath;//"~/play_15.aspx"            Match match = Regex.Match(url, @"~/Play_(\d+).aspx");            if (match.Success)            {                int id = Convert.ToInt32(match.Groups[1].Value);                Context.RewritePath("play.aspx?id=" + id);            }        }