请教泛型方法重载的一个小问题

我用类似PetShop的方式实现三层架构,数据访问层有一个基类DataAccessObjectBase，实现思路如下：

1、两个实体类OrderInfo和OrderDatailInfo。(Model,作为在各层之间传递的数据对象)
2、数据访问层的基类：
public abstract class DataAccessObjectBase<TDomainObject> where TDomainObject : new()
{
    public string ObjectId;
    public string ParentObjectId;
    public string ChildObjectId;

    #region Common StoredProcedure Name List

    public string SelectByIdStoredProcedureName;

    public string SelectDetailObjectStoredProcedureName;
    public string SelectMasterObjectStoredProcedureName;
    #endregion

public abstract void LoadDomainObjectInfo(TDomainObject domainObject, System.Data.IDataReader dr);
public TDomainObject SelectById(System.Guid id)
        {
            Database db = DatabaseFactory.CreateDatabase();
            DbCommand cmd = db.GetStoredProcCommand(SelectByIdStoredProcedureName);
            DataAccessHelper.PopulateIdParamter(db, cmd, id);

            TDomainObject domainObject = new TDomainObject();

            try
            {
                using (IDataReader dr = db.ExecuteReader(cmd))
                {
                    if (dr.Read())
                    {
                        LoadDomainObjectInfo(domainObject, dr);
                    }
                }
            }
            catch (InvalidOperationException ex)
            {
                //if (ExceptionPolicy.HandleException(ex, SR.ExceptionReplacePolicy)) throw;
            }
            catch (DataException ex)
            {
                //if (ExceptionPolicy.HandleException(ex, SR.ExceptionWrapPolicy)) throw;
            }
            return domainObject;
        }

public virtual void LoadDetailObjectInfo<TDetailObject>(TDetailObject detailObject, System.Data.IDataReader dr)
        {
            throw new Exception("The method or operation is not implemented.");
        }

        /// <summary>
        /// 返回当前实体类的子对象，如订单类，则返回的是订单的订单明细
        /// </summary>
        /// <typeparam name="TDetailObject"></typeparam>
        /// <param name="id"></param>
        /// <returns></returns>
        public List<TDetailObject> SelectDetailObject<TDetailObject>(System.Guid id) where TDetailObject : new()
        {
            if( String.IsNullOrEmpty(SelectDetailObjectStoredProcedureName ) ) return null;

            Database db = DatabaseFactory.CreateDatabase();
            DbCommand cmd = db.GetStoredProcCommand(SelectDetailObjectStoredProcedureName);

            DataAccessHelper.PopulateIdParamter(db, cmd, id, ObjectId);

            List<TDetailObject> domainObjectList = new List<TDetailObject>();
            try
            {
                using (IDataReader dr = db.ExecuteReader(cmd))
                {
                    while (dr.Read())
                    {
                        TDetailObject detailObject = new TDetailObject();
                        LoadDetailObjectInfo<TDetailObject>((TDetailObject)detailObject, dr);

                        domainObjectList.Add(detailObject);
                        
                    }
                }
            }
            catch (InvalidOperationException ex)
            {
                //if (ExceptionPolicy.HandleException(ex, SR.ExceptionReplacePolicy)) throw;
            }
            catch (DataException ex)
            {
                //if (ExceptionPolicy.HandleException(ex, SR.ExceptionWrapPolicy)) throw;
            }
            return domainObjectList;
        }

订单数据访问类：继承于DataAccessObjectBase，
重载了抽象的和虚拟的方法，分别如下：
//////////////////////////////////
public override void LoadDomainObjectInfo(OrderInfo order, System.Data.IDataReader dr)
        {
            LoadAdminObjectInfo.LoadOrderInfo(order, dr);
        }

// 请教：这个方法应该如何重载？<=====================
public override void LoadDetailObjectInfo<TDetailObject>(TDetailObject detailObject, IDataReader dr)
        {
           
            LoadAdminObjectInfo.LoadOrderItemInfo(detailObject, dr);
        }

其中LoadAdminObjectInfo，是一个辅助类，有两个方法如下：
public static void LoadOrderInfo(OrderInfo order, System.Data.IDataReader dr)
        {
            order.OrderId = (System.Guid)dr["OrderId"];
            order.SequenceNumber = (System.Int32)dr["SequenceNumber"];
            order.Name = (System.String)dr["Name"];
           
        }
 public static void LoadOrderItemInfo(OrderItemInfo orderItem, System.Data.IDataReader dr)
        {
            orderItem.OrderItemId = (System.Guid)dr["OrderItemId"];
            orderItem.OrderId = (System.Guid)dr["OrderId"];
            orderItem.LocalId = (System.String)dr["LocalId"];
        }

对于具体的数据访问对象，LoadDetailObjectInfo应该如何重载？

posted on 2006-05-29 20:55  学习.NET  阅读(1386)  评论()    收藏  举报