System.Data.Objects.ObjectContextOptions does not contain a definition for DeferredLoadingEnabled

Question

I am working with a sample Entity Framework class library project that uses POCO classes (and an old Northwind-2000 db that I am running on SqlExpress 2012).  This project was created in VS2010 with EF4.1.  I have VS2012 with EF5.0 and EF6.1.  When I try to compile one of the library classes (NorthwindPocoTest) I receive the following error message (images of the error below):
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Error 5 'System.Data.Objects.ObjectContextOptions' does not contain a definition for 'DeferredLoadingEnabled' and no extension method 'DeferredLoadingEnabled' accepting a first argument of type 'System.Data.Objects.ObjectContextOptions' could be found (are you missing a using directive or an assembly reference?)
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What changes can I make so that this library will compile?  The other two libraries in the project compile OK.  Can I change something in the project?  Are there any configurations I can change in VS2012?

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Rich P

Answer 1

I noticed that if I comment out the code in the

public void QueryForCategoryAndLazyLoadProducts()
{
  // ...
}

procedure -- then this library class compiles.  Also, this library is a unit test, if that makes any difference.  But I would still like to know about

context.ContextOptions.DeferredLoadingEnabled = true;

I think this has something to do with Lazy Loading.  Any thoughts appreciated.

---

Rich P

Answer 2

There is no DeferredLoadingEnabled property on the ObjectContextOptions class. You probably want to set the LazyLoadingEnabled property:

context.ContextOptions.LazyLoadingEnabled = true;

Or you could just get rid of the that code since laxy loading is enabled by default.

Deferred loading is a LINQ-to-SQL thing: http://msdn.microsoft.com/en-us/library/system.data.linq.datacontext.deferredloadingenabled(v=vs.110).aspx

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