public bool Usuario_broker(string CodUsu, string Pw)
        {
            bool       rtrn       = false;
            ConexionDb conn       = new ConexionDb();
            var        str_conect = conn.init_Conection();

            using (str_conect)
            {
                SqlCommand command = new SqlCommand(" SELECT USUARIO.CODUSU, USUARIO.LOGIN FROM USUARIO WHERE USUARIO.CODUSU = @CodUsu ", str_conect);
                command.Parameters.AddWithValue("@CodUsu", CodUsu);
                str_conect.Open();
                DataTable dt = new DataTable();
                dt.Load(command.ExecuteReader());
                if (dt.Rows.Count.ToString() == "1")
                {
                    rtrn = true;
                }
                return(rtrn);
            }
        }