Specifying the Items in the CartCreate Request
request, you can add up to ten different items to the cart. The quantity of
each item can be between 1 and 50. That means in one
request, you could add up to five-hundred items (10 items * 50 quantity).
Items are specified in parameter pairs, as follows:
Item.N.ItemIdType=[Item identifier] Item.N.Quantity=[Number of Item.N items]
N is a positive integer. The N value associates the ItemId with the quantity of those items that should be added to the cart, for example:
[An OfferListingId]& Item.1.Quantity=3& Item.2.OfferListingId=
[An OfferListingId]& Item.2.Quantity=5&
This request adds three number 1 items and five number 2 items to the remote shopping cart. You could interchange lines without affecting the end result, for example:
[An OfferListingId]& Item.2.OfferListingId=
[An OfferListingId]& Item.1.Quantity=3& Item.2.Quantity=5&
The values for
do not have to be listed in ascending or descending order, nor do the values of
need to be sequential. You could, for example, use the values, 1, 4, 7 for
N. Also, the value of
is not retained between requests. For that reason, it is permissible to use
Item.1 in a
request and then in a
request, which adds an item to the cart. In these requests, Item.1 can refer to
two completely different items.
The value of adding multiple items to the cart in one request is performance. It takes less time to add ten items in one request than it does to add ten items to the cart in ten separate requests.
You can specify items to add to a cart in the following ways.
|ASIN||An alphanumeric token that uniquely identifies an item sold by Amazon. Amazon assigns ASINs to items. Using OfferListingId is the preferred method of identifying items to add to the cart.|
|OfferListingId||An alphanumeric token that uniquely identifies an
item sold by a seller or merchant. Amazon assigns
OfferListingIds to items. You can find an OfferListingId
example uses OfferListingId to identify the items to add to the cart. An
OfferListingId is returned by the Offers and OfferFull response groups. An
alternative is using an item's ASIN. An ASIN is assigned to every item
offered by Amazon. An OfferListingId is assigned to every item that is
available for sale.
The advantage of using OfferListingId in the
request is that items that cannot be purchased, such as Variation parent
items, do not have OfferListingId's. By using the OfferListingId, you
are assured that an item can be purchased.
Offers and Identifiers
ASINs identify items, such as a Harry Potter book. ASINs do not, however, identify sales information related to those items.
As you can see in the preceding figure, an ASIN identifies an item but not an instance of it that a customer can purchase. Every ASIN can be sold by many merchants. Each merchant lists the condition and price of the item. This combination of data represents an OfferListingId. Taken together, all OfferListingIds are referred to as offers. If an ASIN does not have an OfferListingId, the item cannot be purchased.
For this reason, it is recommended that you add items to a shopping cart by their OfferListingId rather than by their ASIN.