private void FixupPurchaseOrderHeader(PurchaseOrderHeader previousValue) { if (previousValue != null && previousValue.PurchaseOrderDetails.Contains(this)) { previousValue.PurchaseOrderDetails.Remove(this); } if (PurchaseOrderHeader != null) { if (!PurchaseOrderHeader.PurchaseOrderDetails.Contains(this)) { PurchaseOrderHeader.PurchaseOrderDetails.Add(this); } if (PurchaseOrderID != PurchaseOrderHeader.PurchaseOrderID) { PurchaseOrderID = PurchaseOrderHeader.PurchaseOrderID; } } }