Question

I have an element bound to an entity (Contact) that exposes some navigation properties.

I want, that on some action (i.e. a "Load children" button), the Contact should load for all its children and grand children like I can do with an ObjectQuery.Include before the execution; example (pseudo):

DirectCast(element.DataContext, Contact).SubContacts. _
   Include("Address.State"). _
   Load()

I want to be able to shape the results also by reloading items like the example above, not only when querying the model itself.

I think this should of been a part of Entity-Framework in some way.

Answer 1

I m not positive I follow the question, but let me check:

You want to take an entity that you have already loaded, then load a navigation property with include paths for that property. This isn t actually that difficult, as long as you are using the same context that you used to load the first object.

The important point is that whenever you do a query that returns an entity, Entity Framework will automatically link it up with any of its related objects that you already have. So what you really want is to produce a new query that returns the extra data, with some includes.

Every reference in Entity Framework has a method called CreateSourceQuery. It returns an Object Query, so you can use it to do this (sorry, C#):

AlreadyLoadedContact.SubContacts.CreateSourceQuery().Include("Address.State").ToList();

The ToList call executes the query, and Entity Framework will take all the results and automatically add them to you SubContacts EntityCollection.

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