Using proxy classes to load data from a database?

c# entity-framework poco proxy-classes

Question

In Entity Framework 4 Is it possible to choose to load some queries into a POCO without it using proxy classes? (For the purpose of caching that object for future read only use). I am using the Repository - Service pattern.

By this I mean:

var order = _orderService.GetById(1);
// after order is loaded then we can see in the debugger that:
// order.Customer is of type System.Data.Entity.DynamicProxy.Customer_17631AJG_etc

What I want is for the order.Customer to actually use the POCO type MyApp.Models.Entities.Customer instead of a proxy to that type.

EDIT: Based on Ladislav's suggestion to add a "GetUnproxied" method to the Repository, I've made this change:

// this is the current method that must return a DynamicProxy
public IQueryable<T> GetQuery()
{
    return ObjectSet.AsQueryable();
}

// this is the new additional method that must return the plain POCO
public IQueryable<T> GetReadOnly()
{
    ObjectContext.ContextOptions.ProxyCreationEnabled = false;
    var readOnly = ObjectSet.AsQueryable();
    ObjectContext.ContextOptions.ProxyCreationEnabled = true;
    return readOnly;
}

Is this correct?

It does not look thread safe to me. Both methods use the same ObjectContext instance, so it might be possible for ProxyCreationEnabled == false to happen on one thread and then public IQueryable<T> GetQuery() to be called on another thread - which would suddenly mean that the proxy method could return the non proxied object.

1
7
1/5/2015 4:03:44 PM

Accepted Answer

Use this before you query data to turn off proxy creation

context.ContextOptions.ProxyCreationEnabled = false;

I think it can be also turned off globally in EDMX designer.

Update:

This applied to ObjectContext. With DbContext the code is:

context.Configuration.ProxyCreationEnabled = false;

plus I do not see any option in the edmx designer

16
1/5/2015 3:33:42 PM


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