How do I handle UpdateException - 'Violation of PRIMARY KEY constraint' on Entity Framework?

Since I got an upvote I looked back how I solved this. So here is what I did:

// Exception number 2627 = Violation of %ls constraint '%.*ls'. Cannot insert duplicate key in object '%.*ls'.
// Exception number 2601 = Cannot insert duplicate key row in object '%.*ls' with unique index '%.*ls'.
// See http://msdn.microsoft.com/en-us/library/cc645603.aspx for more information and possible exception numbers
if (innerException != null && (innerException.Number == 2627 || innerException.Number == 2601))
{
    // Resolve the primary key conflict by refreshing and letting the store win
    // In order to be able to refresh the entity its state has to be changed from Added to Unchanged
    ObjectStateEntry ose = ex.StateEntries.Single();
    this.ObjectStateManager.ChangeObjectState(ose.Entity, EntityState.Unchanged);
    base.Refresh(RefreshMode.StoreWins, ose.Entity);

    // Refresh addedChanges now to remove the refreshed entry from it
    addedChanges = this.ObjectStateManager.GetObjectStateEntries(System.Data.EntityState.Added).Where(s => !s.IsRelationship);
}
else
{
    throw;
}

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Edit:

Note that UpdateException has been renamed to DbUpdateException starting with EF 4.1.