Disabled lazy loading EF not working correctly?

Question

I'm trying to return several lists of elementes through a WCF Service and I want to control every object loaded in the list to avoid stack overflow exceptions on serializing and returning the result.

I populate this lists with LINQ to Entities and I have disabled Lazy Loading for the EF model... but when I try it many of the references are populated and it throws an exception when trying to return the List.

This is an example:

public class DelegacionesDAO : IDelegacionesDAO
    {
        Model.Entities entities = new Model.Entities();

        public DelegacionesDAO()
        {
            entities.ContextOptions.ProxyCreationEnabled = false;
            entities.ContextOptions.LazyLoadingEnabled = false;
        }

    public List<Model.Things> GetDelegaciones()
            {
                IQueryable<Model.Things> thingsList= from things in entities.Things
                                                     select things;

                return thingsList.ToList<Model.Things>();
            }
}

This table "Things" is referenced by other like "Persons" (who have things) and this is the problem, when I try to return it, every "Thing" has a list of "Persons" and beyond.

Am I missing anything??

Thanks in advance!

Edit: Added some more code. Now it's working... I think it loads every navigation property when you try to "watch" it even if it's not loaded :-S

Now I only have the doubt if I'm doing it well by creating the entities instance in the constructor to use it through WCF.

Answer 1

Don't work with long-living contexts (field "entities in your case) when working with WCF:

• It is not thread safe (especially calling SaveChanges from different threads while other threads are preparing data)
• The context collects and associates every entity you are loading (as long as you don't explicitly use MergeOption.NoTracking)

Answer 2

If you have Lazy Loading turned off you have to tell EF to load the references.

Try this:

var thingsList= (from things in entities.Things
                select things) as ObjectQuery<Model.Things>;
thingsList = thingsList.Include("Persons"); //name of navigation property

return thingsList.ToList<Model.Things>();