NHibernate QueryOver 與 SelectList

Question

我對一張表有多個查詢。 由於並非所有列/屬性都需要，我在 select 列表的幫助下指定列。 以下面的方法為例。 這個方法有效

public IEnumerable<ResultDto> GetEntityAsDto(eStatusBinderProduktion fromState, eStatusBinderProduktion toState)
{
    EntityClass entityAlias = null;
    ResultDto resultAlias = null;

    var query = Session.QueryOver<EntityClass>(() => entityAlias)
      .Where(() => entityAlias.ProduktionStatus >= (byte)fromState)
      .And(() => entityAlias.ProduktionStatus <= (byte)toState);

    query.SelectList(list => list
         .Select(() => entityAlias.PrimaryID).WithAlias(() => resultAlias.PrimaryID)
         .Select(() => entityAlias.SecondaryID).WithAlias(() => resultAlias.SecondaryID)
         );

    return query.TransformUsing(Transformers.AliasToBean<ResultDto>())
          .List<ResultDto>();
}

由於我需要在多個方法中定義 SelectList，我試圖將 SelectList 移動到一個單獨的方法中。

以下代碼不起作用，NHibernate 拋出異常

NHibernate.QueryException：'無法解析屬性：entity.PrimaryID of：MyProjectNamespace.DAL.Interfaces.Entities.EntityClass'“

public IEnumerable<ResultDto> GetEntityAsDto(eStatusBinderProduktion fromState, eStatusBinderProduktion toState)
{
    EntityClass entityAlias = null;
    ResultDto resultAlias = null;

    var query = Session.QueryOver<EntityClass>(() => entityAlias)
      .Where(() => entityAlias.ProduktionStatus >= (byte)fromState)
      .And(() => entityAlias.ProduktionStatus <= (byte)toState);

    MapPropertiesOfEntityToResult(entityAlias, resultAlias, query);

    return query.TransformUsing(Transformers.AliasToBean<ResultDto>())
          .List<ResultDto>();
}

private void MapPropertiesOfEntityToResult(EntityClass entity, ResultDto resultAlias, IQueryOver<EntityClass, EntityClass> query)
{
  query.SelectList(list => list
   .Select(() => entity.PrimaryID).WithAlias(() => resultAlias.PrimaryID)
   .Select(() => entity.SecondaryID).WithAlias(() => resultAlias.SecondaryID)
    );
}

附加信息：
- 映射是正確的
- 表格充滿了測試數據

Answer 1

我們不需要別名來填充 SelectList。 我們可以從IQueryOver<TRoot,TSubType>的 Type 參數中獲益：

//private void MapPropertiesOfEntityToResult(EntityClass entity
//   , ResultDto resultAlias, IQueryOver<EntityClass, EntityClass> query)
private void MapPropertiesOfEntityToResult( // no need for entity
      ResultDto resultAlias, IQueryOver<EntityClass, EntityClass> query)
{
  query.SelectList(list => list
   //.Select(() => entity.PrimaryID).WithAlias(() => resultAlias.PrimaryID)
   //.Select(() => entity.SecondaryID).WithAlias(() => resultAlias.SecondaryID)
   .Select(entity => entity.PrimaryID).WithAlias(() => resultAlias.PrimaryID)
   .Select(entity => entity.SecondaryID).WithAlias(() => resultAlias.SecondaryID)
    );
}

該entity現在是傳遞的Function的參數，其類型來自IQueryOver定義