Question

I am mapping some pre-existing Business Objects to our database using Entity Framework. These object were originally using a home-grown data access method, but we wanted to try out Entity Framework on it now that it is using Code-First. It was my expectation that this would be fairly simple, but now I am having some doubts.

I am trying to use only attributes to accomplish this so that I don’t have some of the mapping here, some of it there, and still more of it over there….

When I query for entities, I am getting System.Data.Entity.DynamicProxies.MyClass_23A498C7987EFFF2345908623DC45345 and similar objects back. These objects have the data from the associated record there as well as related objects (although those are DynamicProxies also).

What is happening here? Is something going wrong with my mapping? Why is it not bringing back MyBusinessObject.MyClass instead?

Answer 1

That has nothing to do with mapping. Those types you see are called dynamic proxies. EF at runtime derives class from every type you map and use it instead of your type. These classes has some additional internal logic inside overriden property setters and getters. The logic is needed for lazy loading and dynamic change tracking of attached entities.

This behaviour can be turned off in context instance:

context.Configuration.ProxyCreationEnabled = false;

Your navigation properties will not be loaded automatically once you do this and you will have to use eager loading (Include method in queries) or explicit loading.