public void UpdateGame(Games game)
{
EntityKey key = null;
object original = null;
using (EntitiesContx contx = new EntitiesContx ())
{
try
{
Games g = new Games();
g.GameName = game.GameName;
g.GameDescription = game.GameDescription;
g.GameId = game.GameId;

EntityKey _relationshipKey = new EntityKey();
_relationshipKey.EntityContainerName = typeof(EntitiesContx).Name;
_relationshipKey.EntitySetName = typeof(Genre).Name;
_relationshipKey.EntityKeyValues = new EntityKeyMember[1] { new EntityKeyMember(“GenreId”, game.Genre.GenreId) };

g.GenreReference = new EntityReference();
g.GenreReference.EntityKey = _relationshipKey;

contx.AttachTo(typeof(Games).Name, g);

contx.SaveChanges();
}
catch (Exception ex)
{

throw;
}
}

}

any help

Alk.

CompanyGroup is pretty simple. It has a name and it has a Company object.

I started with this:

public static void Add(CompanyGroup item)
{
try
{
using (Entities scope = new Entities())
{
scope.AddToCompanyGroup(item);
scope.SaveChanges();
}
}
catch (Exception ex)
{
LogException(ex, item);
throw;
}
}

And got this error:

{“An entity object cannot be referenced by multiple instances of IEntityChangeTracker.”}

So, I added this between lines 6 and 7:

(IEntityWithChangeTracker)item).SetChangeTracker(null);

That rewarded me with:

{“The object cannot be added to the ObjectStateManager because it already has an EntityKey.
Use ObjectContext.Attach to attach an object that has an existing key.”}

So I changed

scope.AddToCompanyGroup(item);

to scope.Attach(item);

Now it complained about:

{“An object with a temporary EntityKey value cannot be attached to an object context.”}

(beginning to sound like some of the girls I dated in my youth, but I digress)

So I made the entity key null (didn’t work) and used the method to create new (didn’t work, either)

Along the way, I got this error, too:

{“The source query for this EntityCollection or EntityReference cannot be returned when the related object is in either an
added state or a detached state and was not originally retrieved using the NoTracking merge option.”}

The Solution?

Replace the core, lines 7 and 8, with:

CompanyGroup newcg = new CompanyGroup();
newcg.GroupName = item.GroupName;
newcg.Company = scope.Company.Where(c => c.CompanyID == item.Company.CompanyID).First();

scope.AddToCompanyGroup(newcg);
scope.SaveChanges();

Essentially, I took the data passed via ‘item’, and moved it to newly created object of the same type that introduces the same
scope as the one used in the Add.