如何检索基类（实体框架）？ [英] How to retrieve base class only (entity framework)?

问题描述

我一直在刮擦我的头一段时间了...
我有一个Consumer类和一个BillableConsumer类继承了Consumer。他们都是消费者的一部分。问题是，以下查询：

  Consumer consumer =（from c in _ctx.Consumers where c.ID = id select c ）。第一（）; 
  

返回一个BillableConsumer实例！与这个查询一样：

  BillableConsumer bconsumer =（从_ctx.Consumers.OfType< BillableConsumer>（）中的c）其中c .ID = id select c）.First（）; 
  

如何返回只有基类的实例？ （这些是数据存储中的单独表格）。

解决方案

是的，这有点棘手。

但是我做了一个提示在这一段时间后

希望这有助于

Alex

I've been scratching my head here for a while now... I have a Consumer class and a BillableConsumer class that inherits Consumer. They are both a part of the Consumers set. The problem is that this following query:

Consumer consumer = (from c in _ctx.Consumers where c.ID = id select c).First();

returns a BillableConsumer instance! Just the same as this query:

BillableConsumer bconsumer = (from c in _ctx.Consumers.OfType<BillableConsumer>() where c.ID = id select c).First();

How can I return an instance of just the base class? (these are separate tables in the data store).

解决方案

Yes this is a little tricky.

But I did a tip on this a while back

Hope this helps

Alex

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