static public string StringQuery(string _query)
 {
            string result = "";
           
try {
                SqlDataAdapter DA = new SqlDataAdapter(_query, con);
                DataSet DS = new DataSet();
                DA.Fill(DS, "DS");
                result = DS.Tables["DS"].Rows[0][0].ToString();
}
catch (Exception e) {
//some log?
}
return result;
}