/// <summary>
        /// get an instance of object
        /// </summary>
        /// <param name="myID"></param>
        public dh_subcategorias getObject(int id_subcategoria)
        {
            dh_subcategorias dh_subcat = new  dh_subcategorias();
            CnxBase          myBase    = new CnxBase();
            string           reqSQL    = "SELECT id_subcategoria,id_categoria,subcategoria FROM dh_subcategorias WHERE (id_subcategoria=" + id_subcategoria + ")";

            try
            {
                NpgsqlConnection myConn    = myBase.OpenConnection(myBase.cnxString);
                NpgsqlCommand    myCommand = new NpgsqlCommand(reqSQL, myConn);
                NpgsqlDataReader myReader  = myCommand.ExecuteReader();
                if (myReader.Read())
                {
                    dh_subcat.id_subcategoria = Convert.ToInt32(myReader[0]);
                    dh_subcat.id_categoria    = Convert.ToInt32(myReader[1]);
                    dh_subcat.subcategoria    = myReader[2].ToString();
                }
                myBase.CloseConnection(myConn);
            }
            catch (Exception myErr)
            {
                throw (new Exception(myErr.ToString() + reqSQL));
            }
            return(dh_subcat);
        }
        /// <summary>
        /// add a record
        /// </summary>
        /// <param name="myID"></param>
        public void Insert(dh_subcategorias mydh_subcat)
        {
            CnxBase myBase = new CnxBase();
            string  reqSQL = "INSERT INTO dh_subcategorias (id_categoria, subcategoria) VALUES (" + mydh_subcat.id_categoria + ",'" + mydh_subcat.subcategoria + "')";

            try
            {
                NpgsqlConnection myConn    = myBase.OpenConnection(myBase.cnxString);
                NpgsqlCommand    myCommand = new NpgsqlCommand(reqSQL, myConn);
                myCommand.ExecuteNonQuery();
                myBase.CloseConnection(myConn);
            }
            catch (Exception myErr)
            {
                throw (new Exception(myErr.ToString() + reqSQL));
            }
        }
        /// <summary>
        /// modify a record
        /// </summary>
        public void Update(dh_subcategorias mydh_subcat)
        {
            CnxBase myBase = new CnxBase();
            string  reqSQL = "UPDATE dh_subcategorias SET id_subcategoria=" + mydh_subcat.id_subcategoria + ",id_categoria=" + mydh_subcat.id_categoria + ",subcategoria='" + mydh_subcat.subcategoria + "' WHERE (id_subcategoria=" + mydh_subcat.id_subcategoria + ")";

            try
            {
                NpgsqlConnection myConn    = myBase.OpenConnection(myBase.cnxString);
                NpgsqlCommand    myCommand = new NpgsqlCommand(reqSQL, myConn);
                myCommand.ExecuteNonQuery();
                myBase.CloseConnection(myConn);
            }
            catch (Exception myErr)
            {
                throw (new Exception(myErr.ToString() + reqSQL));
            }
        }