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How do I know if the OrderID is a single or multiple line item order in the GetSellerTransactions response?
Determining single line items vs multiple line items in GetSellerTransactions
Before version 705 <ContainingOrder> was ONLY returned if the order line item was part of a Combined Payment order. To determine if an order is a single line item or multiple line item, follow the steps below:
1. In your GetSellerTransactions call, make sure to include this field and set it to true, <IncludeContainingOrder>true</IncludeContainingOrder>. This will ensure you get back the <ContainingOrder> in every call.
2. In the response you will get back these 4 fields:
*Note - OrderLineItemID = ItemID-TransactionID. For a single line item order, the OrderID value is identical to the OrderLineItemID value that is generated upon creation of the order line item. For a Combined Payment order, the OrderID value is created by eBay when the buyer or seller (sharing multiple, common order line items) combines multiple order line items into a Combined Payment order through the eBay site.
3. So you will need to compare OrderID with OrderLineItemID, and if they are NOT equal then it's a combined payment order (true order) and if they are equal it is a single line item order (fake order).
GetSellerTransactions(Input IncludeContainingOrder): http://developer.ebay.com/DevZone/XML/docs/Reference/ebay/GetSellerTransactions.html#Request.IncludeContainingOrder
.ContainingOrder ): http://developer.ebay.com/DevZone/XML/docs/Reference/ebay/GetSellerTransactions.html#Response.TransactionArray.Transaction.ContainingOrder