在线交易如何通知应用程序或服务提供商品或服务？

Question

I've been searching but have not been able to find this out. Essentially, when you for example buy credits for a game through PayPal or Google Checkout, how is the information of a successful transaction translated from PayPal or Google Checkout so that the Web Site knows to access its database and credit you those credits?

Thanks

Answer 1

PayPal has a multitude of systems for their payment processes, I have personally used the IPN or Instant Payment Notification system. How this works is, you setup a page on your website that PayPal will visit when you receive a payment. When visiting the site, PayPal visits with GET or POST values, which your page should then report back to the site and verify.

Once the values are verified as truly coming from PayPal, you can use those values to credit the account and store the purchase information.

I have used this to credit players on my games with credits, and generally I create product IDs using a system that I can then break apart on the back end, and verify against a product database -- so, say my system was 1credit5 meaning 1 credit for 5 dollars, they couldn't use a plugin like Firebug to edit the form to 100000credit5 (or 100,000 credits for $5) because that would not show up as a valid product, and I would be notified as to the fraud.

I'm not sure about any other payment system, but I know there are quite a few tutorials on PayPal's IPN system.

Answer 2

通常，通知是通过API完成的。