public static string getSelectedIDs(Repeater Rpt_)        {            string res = string.Empty;            foreach (RepeaterItem rtpItem in Rpt_.Items)            {                HtmlInputCheckBox obj = rtpItem.FindControl("checkbox") as HtmlInputCheckBox;                if (obj != null)                {                    if (obj.Checked == true)                    {                        res += obj.Value.ToString() + ",";                    }                }            }            if (!string.IsNullOrEmpty(res))            {                res = res.Remove(res.LastIndexOf(‘,‘));            }            return res;        }