Chinook.Model.Customer.FixupInvoices C# (CSharp) Метод

        private void FixupInvoices(object sender, NotifyCollectionChangedEventArgs e)
        {
            if (e.NewItems != null)
            {
                foreach (Invoice item in e.NewItems)
                {
                    item.Customer = this;
                }
            }
    
            if (e.OldItems != null)
            {
                foreach (Invoice item in e.OldItems)
                {
                    if (ReferenceEquals(item.Customer, this))
                    {
                        item.Customer = null;
                    }
                }
            }
        }