DataSet fileNameDs = DbHelper.excuteSqlResultDataSet(strSql);

            if (fileNameDs != null && fileNameDs.Tables.Count > )

            {

                DataTable fileNameDt = fileNameDs.Tables[];

                if (fileNameDt != null && fileNameDt.Rows.Count > )

                {

                    return fileNameDt.Rows[][].ToString();

                }

            }