尝试访问传递到IQueryable实现程序中的表达式 [英] Trying to access the Expression passed into an IQueryable implementor

问题描述

我正在创建实现IQueryable的存储库.客户端按如下方式调用此存储库:

I am creating a Repository that implements IQueryable. The client calls this Repository as follows:

OrderRepository.AsQueryable().Where(x => x.ID == 123);

因此，据我了解，IQueryable的要点是允许实现者在获取数据/实体之前访问传递给它的表达式.

例如，使用上面的代码，OrderRepository会知道要从ID = 123的数据源执行特定的提取.

如果没有AsQueryable，OrderRepository将需要获取所有订单，然后客户端将应用Where函数来将完整的Orders结果集过滤为仅ID = 123的那些订单.

我现在的主要问题是我似乎在通过存储库访问表达式时遇到问题.

我对此的理解正确吗?我可能会缺少什么?

So the point of IQueryable as I understand it is that is allows the implementor to access the expression being passed to it before fetching the data/entities.

For example, with the code above, OrderRepository would know to perform a specific fetch from it''s datasource where ID=123.

Without AsQueryable the OrderRepository would need to fetch all orders and *then* the Where function would be applied by the client to filter the full Orders result set down to only those orders where ID=123.

My main problem right now is I seem to be having problems accessing the expression through the Repository.

Is my understanding of this correct? What might I be missing?

推荐答案

http ://stackoverflow.com/questions/1578778/using-iqueryable-with-linq [ ^ ]

此链接应有助于回答您的一些问题.

http://stackoverflow.com/questions/1578778/using-iqueryable-with-linq[^]

This link should help answer some of your questions.

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