asp.net连接达梦数据库时(DM7),用web方式，一直提示 6001，communication error


   #region 执行可变带参数的SQL语句
        /// <summary>
        /// 执行可变带参数的SQL语句
        /// </summary>
        /// <param name="Sqlstr">SQL语句</param>
        /// <param name="param">可变参数对象数组</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(String Sqlstr, params IDataParameter[] parameters)
        { 
            String ConnStr = "Server=localhost;USER ID=SYSDBA;PASSWORD=SYSDBA";
            try
            {
                Dm.DmConnection conn = new Dm.DmConnection(ConnStr);          
                conn.Open();
                DmCommand cmd = conn.CreateCommand();                cmd.CommandText = Sqlstr;
                cmd.Parameters.AddRange(parameters);
                return cmd.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            return 0;
        
        }
        #endregion