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[英]Calling an object constructor from NHibernate QueryOver SelectList
[英]NHibernate QueryOver with SelectList
我对一张表有多个查询。 由于并非所有列/属性都需要,我在 select 列表的帮助下指定列。 以下面的方法为例。 这个方法有效
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>();
}
由于我需要在多个方法中定义 SelectList,我试图将 SelectList 移动到一个单独的方法中。
以下代码不起作用,NHibernate 抛出异常
NHibernate.QueryException:'无法解析属性: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:
- 映射是正确的
- 表格充满了测试数据
我们不需要别名来填充 SelectList。 我们可以从IQueryOver<TRoot,TSubType>
的 Type 参数中获益:
//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)
);
}
该entity
现在是传递的Function
的参数,其类型来自IQueryOver
定义
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