Hi there,

as I understand it, DoNotPerformAddIfPresent will prevent entities with the same PK definition of being added to an EntityCollection.

I did the following test with an entity

            
Me.Auftragsposition.AuftragsPosDokumente.DoNotPerformAddIfPresent = True
_auftragsPosDoc = New MyAuftragsPosDokumenteEntity(Me.Auftragsposition.AuftragsNr, Me.Auftragsposition.Auftragsposition, 14)
_auftragsPosDocTmp = New MyAuftragsPosDokumenteEntity(Me.Auftragsposition.AuftragsNr, Me.Auftragsposition.Auftragsposition, 14)
Me.Auftragsposition.AuftragsPosDokumente.Add(_auftragsPosDoc)
Me.Auftragsposition.AuftragsPosDokumente.Add(_auftragsPosDocTmp)

As you can see I am using the PK constructor of the entity and after the operation I see two identical elements in the collection. - Am I missing on something?

Best regards

Set IsNew to false and try again. Equals checks the PK values when the entity is not new, otherwise an instance check is performed.

Dear Otis,

thank you for your reply!

Added new entites already have a PK set, is it possible to have the EntityCollection proof these elements? In my case, entites are being added by a grid through databinding (NewLine function) and not in code. I tried removing these entities by hand but this is causing a lot of troubles with the various events being fired. Could it be possible to do this test on new objects? Can you suggest any workaround?

Best regards

What I forgot to say is: setting IsNew to false works (of course). However, wouldn't setting isNew to false prevent the Adapter from attempting to save these entities using an Insert and it would instead try an update, Am i right on this? Also, the elements are added via the grid, so I have no control on the elements before they are added.

You can also test if the PK is already there and if not, add the entity. Here's an example:

// newCustomerEntity is filled with data, but new, now check if it's already in the collection.
newCustomerEntity.IsNew = false;
if(customers.IndexOf(newCustomerEntity)<0)
{
// not there yet.
newCustomerEntity.IsNew = false;
customers.Add(newCustomerEntity);
}