I'm using Merchello 2.6 to build an online shop with shipment that seems having contradiction with Merchello's OrderItem.

• Background:

  The situation is that when the customer makes an purchase invoice on 10 Qty on 1 Product (1 SKU), creating an order after payment captured, the shop needs to split the shipment of these 10 Qty same-SKU items in the same invoice with different carriers! (due to their business restriction, e.g. ship 1 Qty with Carrier A, ship 3 Qty with Carrier B). However, Merchello by default only let user split the shipment by line-item, while this partial shipment inside 1 line-item seems not supported.

• Problem - SKU is Key for LineItem

  Then I try to split the order line items into the splits they need in the same order,

  e.g. this code just try to split a SKU with 10 Qty into 10 Line Items.

  [Obsolete("It won't work due to conflict with Merchello Core. Leave Code here as reference only", true)]
  private static void SplitOrderLineItemsByQty(IOrder order)
  {
      List<OrderLineItem> newLineItems = new List<OrderLineItem>();
      var itemsToSplit = order.Items.Where(x
          => x.Quantity > 1
          && x.LineItemType == LineItemType.Product
          && x is OrderLineItem)
      .Cast<OrderLineItem>();
      for (int i = 0; i < itemsToSplit.Count(); i++)
      {
          var itemToSplit = itemsToSplit.ElementAt(i);
          for (int iSplit = 1; iSplit < itemToSplit.Quantity; iSplit++)
          {
              newLineItems.Add(new OrderLineItem(itemToSplit.LineItemType, itemToSplit.Name, itemToSplit.Sku, 1, itemToSplit.Price,
                  itemToSplit.ExtendedData)
              {
                  // Don't assign value for new splited items
                  //Key = itemToSplit.Key,
                  //ContainerKey = itemToSplit.ContainerKey,
                  //ShipmentKey = itemToSplit.ShipmentKey,
                  //BackOrder = itemToSplit.BackOrder,
                  //Exported = itemToSplit.Exported,
                  //UpdateDate = itemToSplit.UpdateDate,
                  //CreateDate = itemToSplit.CreateDate
              });
          }
          itemToSplit.Quantity = 1;
      }
  
  
  order.Items.Add(newLineItems);
  
  
  }
  

Since the order.Items is LineItemCollection

class LineItemCollection : NotifiyCollectionBase<string, ILineItem>

and the key is exactly SKU (See https://github.com/Merchello/Merchello/blob/v2.6.0/src/Merchello.Core/Models/LineItemCollection.cs#L193), my sample code won't work! It only add the Qty for adding same SKU; or throw exception due to attempt on adding same-key-item to the collection.

Can I have some good directions or hints on how should it be handled, so the line-item can be split into multiple shipments?