Input string was not in a correct format.

Line 655:    {
Line 656:        JobCode j = new JobCode();Line 657:        DataTable dt_subcode = j.Search_Subcode(Convert.ToInt32(hdnJobCode_ID.Value), hdnSearchCode.Value.ToString());Line 658:        if (dt_subcode.Rows.Count == 0)
Line 659:        {