DataReader转换为实体的应用

 －－－－DataReader转换为实体的泛型类－－－
        注意 数据库表字段名和实体类相同
        public class EntityTranslate
        {
            /// 用class关键字表示约束为引用类型
            /// 用struct关键字表示约束为值类型
            /// new()默认构造函数约束：如果需要在泛型类型内部实例化类型参数的对象，
           ///就必须对类型参数加以默认构造函数约束，除此之外别无选择。
          //执行查询返回对象集合 
          public static List<TEntity> Translate<TEntity>(IDataReader reader) where TEntity : class, new() 
            {
                List<TEntity> list = new List<TEntity>();
                Type entityType = typeof(TEntity);
                //创建实例
                object entity = Activator.CreateInstance(entityType);
                List<string> attributes = new List<string>();
                Dictionary<string, PropertyInfo> dic = new Dictionary<string, PropertyInfo>();
                foreach (PropertyInfo info in entityType.GetProperties())
                {
                    dic.Add(info.Name, info);
                }

                string columnName = string.Empty;
                //object[] attributes = info.GetCustomAttributes(true);
                while (reader.Read())
                {
                    TEntity t = new TEntity();
                    foreach (KeyValuePair<string, PropertyInfo> attribute in dic)
                    {
                        columnName = attribute.Key;
                        int filedIndex = 0;
                        while (filedIndex < reader.FieldCount)
                        {

                            if (reader.GetName(filedIndex) == columnName)
                            {
                                attribute.Value.SetValue(t, reader[filedIndex], null);
                                break;

                            }
                            filedIndex++;


                        }
                    }
                    list.Add(t);

                }
                return list;

            }
        }
      实现代码：
       public void ReaderToEntity()
        {
            string sql = "select * from T_User";
            IDataReader reader = DAO.GetReader(sql);
            List<User> list = EntityTranslate.Translate<User>(reader);
            foreach (User user in list)
            {
                Console.WriteLine("用户ID:" + user.Id.ToString() + " 用户名：" 
                + user.UserName + " 密码:" + user.UserPwd);
            }
            reader.Close();
        }