/// <summary>
        /// 返回单独实体
        /// </summary>
        /// <returns></returns>
        public T ToSingleObject()
        {
            T retObj = default(T);

            using (IDataReader reader = this.ToDataReader())
            {
                if (reader == null)
                {
                    return(retObj);
                }

                EntityMapper <T, TableSchema> map = new EntityMapper <T, TableSchema>(includeTables);
                if (reader.Read())
                {
                    retObj = map.ConvertObject(reader);
                }
                reader.Close();
            }

            return(retObj);
        }
        /// <summary>
        /// 返回查询的结果集
        /// </summary>
        /// <returns></returns>
        public List <T> ToList()
        {
            var list = new List <T>();

            using (IDataReader reader = this.ToDataReader())
            {
                if (reader == null)
                {
                    return(list);
                }

                EntityMapper <T, TableSchema> map = new EntityMapper <T, TableSchema>(includeTables);

                while (reader.Read())
                {
                    list.Add(map.ConvertObject(reader));
                }
                reader.Close();
            }

            return(list);
        }