Пример #1
0
        private List <T> ToList(DbDataReader reader, EntityDescription description)
        {
            List <T> list = new List <T>(Initializer.Instance.DefaultEntityListLen);

            string[] names = DataExtensions.GetColumnNames(reader);

            while (reader.Read())
            {
                T instance = GetSingle(reader, description, names);
                list.Add(instance);
            }
            return(list);
        }
Пример #2
0
        public T ToSingle(DbDataReader reader)
        {
            if (reader.Read())
            {
                EntityDescription description = EntityDescriptionCache.Get(typeof(T));
                string[]          names       = DataExtensions.GetColumnNames(reader);

                return(GetSingle(reader, description, names));
            }
            else
            {
                return(default(T));
            }
        }
Пример #3
0
        /// <summary>
        /// 供实体加载器使用的内部方法,请不要在代码中调用!
        /// </summary>
        /// <param name="dataSource"></param>
        /// <param name="len"></param>
        /// <param name="kvs"></param>
        /// <returns></returns>
        public static int[] CreateNameMapIndex(object dataSource, int len, params KeyValuePair <int, string>[] kvs)
        {
            string[]     names  = null;
            DbDataReader reader = dataSource as DbDataReader;

            if (reader != null)
            {
                names = DataExtensions.GetColumnNames(reader);
            }
            else
            {
                names = DataExtensions.GetColumnNames((DataTable)dataSource);
            }


            // 优化这段代码的性能 (性能提升 60%)
            //int[] colIndex = new int[19];
            //colIndex[0] = DataExtensions.FindIndex(names, "rid");
            //colIndex[1] = DataExtensions.FindIndex(names, "intA");
            //colIndex[2] = DataExtensions.FindIndex(names, "timeA");
            //colIndex[3] = DataExtensions.FindIndex(names, "moneyA");
            // ............................

            int[] colIndex = new int[len];

            foreach (var kv in kvs)
            {
                int index = -1;

                for (int i = 0; i < names.Length; i++)
                {
                    if (names[i] != null &&
                        string.Compare(names[i], kv.Value, StringComparison.OrdinalIgnoreCase) == 0)
                    {
                        index    = i;
                        names[i] = null;                            // 节省后续查找时间
                        break;
                    }
                }
                colIndex[kv.Key] = index;
            }
            return(colIndex);
        }