Where Do I Find the Values for the NVPCodec's Other Parameters?

[kIsaak81]

I am working to create an e-commerce site for a client. I am using code from the tutorial Getting Started with ASP.NET 4.5 Web Forms. Everything went great until I implemented the PayPalFunctions class. The NVPCodec class is asking for two arguments; a string and an integer. What are the numbers are associated with these strings? Here is a little bit of sample code:

Dim encoder As New NVPCodec()
encoder("METHOD") = "SetExpressCheckout"

What number is associated with "METHOD"?

[MAGICMIME]

can you double check if it is asking for NVP/SOP API CREDENTIALS.