Integration Guide

Table Of Contents
Website Payments Standard Integration Guide September 2008 243
5
Third-Party Shopping Carts – The
Cart Upload Command
This chapter describes how to develop a third-party shopping cart that is compatible with
PayPal and Website Payments Standard.
N OTE: If you are not a third-party developer, you can easily add a PayPal Shopping Cart
which is hosted by PayPal to your site. See Chapter 4, “The PayPal Shopping Cart –
Add to Cart and View Cart Buttons.”
Read the following topics to learn more about third-party shopping carts:
z “How A Third Party Shopping Cart Works” on page 243
z “Integrating PayPal with Third Party Shopping Carts” on page 249
How A Third Party Shopping Cart Works
This example shows how a third party shopping cart works with PayPal and Website Payments
Standard. The example merchant has the following account profile settings:
z PayPal Account Optional is turned on. The buyer can pay without an existing PayPal
account and is offered the chance to sign up for one after completing the payment.
For more information, see “PayPal Account Optional” on page 276.
z Shipping Calculations have been set up. PayPal calculates the shipping charges
automatically and adds them to the order.
For more information, see “Automatic Calculation of Shipping Charges (U.S. Merchants
Only)” on page 290 or “Automatic Calculation of Shipping Charges (non-U.S. Merchants
Only)” on page 304.
z Auto Return is turned off. Buyers must click a Return to Merchant button to redirect their
browsers to the merchant website after completing their payments with PayPal.
For more information, see “Auto Return” on page 271.
What The Buyer Sees With Third Party Shopping Carts
Bob is shopping for photos on the DesignerFotos website. He selects several photos for
purchase by clicking the Add to Cart button underneath each one.