checkout express

Jul 4, 2011 at 6:06 PM

Hi, checkout express is missing.

Can you give examples ?




May 5, 2012 at 5:30 AM

Yes, I'd like to see an example as well. It's not the same process as the direct payment. I'm happy for the contribution, but without proper documentation/examples of usage, it's an annoying game of figuring out the source to do what should be a simple process.

May 6, 2012 at 12:13 AM

Just figured out that the usage of the classes mimics somewhat how the PalPal API system works. Read here:, then look up the 3 method calls in the API for more details. Found this link also which may be of some use:

May 6, 2012 at 4:40 AM

Sorry Guys,

I was too busy to reply. Yes james, I tried to create as close to the Paypal Soap API. 

Yeah I know, there is no docs, I am looking for someone to write good docs.

I am working on more enhanced library which will work on .net4,, sl, & wp7.

Already added amazon s3 api, but still missing docs, that's why I haven't uploaded it here.

I will notify you once I launced it.



Anwar Javed


May 7, 2012 at 4:19 AM
Edited May 7, 2012 at 4:21 AM


Ok, thanks. Good job on the API, its very easy to use once you properly understand how the express checkout works (and by spending lots of time looking at how the API works ;) ). I have to recompile the DLL to .NET 4.0 because of the security conversion issue with .NET 2.0 regarding overriding a method on the exception class.

For anyone else interested, you have to read this first to understand the express checkout process:

To get it to work: 

1. Recompile the source: Had to create a new .NET 4.0 class library project and add all the source files (don't forget the 'Properties' folder also [overwrite the new files with the source]), then add the "System.Web" reference.  Locate "InvalidFieldException.cs", line 98, comment it out, and use "[System.Security.SecurityCritical]" instead.  Should be good to go! ;)

2. Go to your PayPal SandBox account: My Account => Profile => API Access =>View API Signature
    (you will need this when querying the web service)

3. If you read the "how-to" via the link above, you'll figure out the rest. ;) You'll need to start with this:

            var expressCheckout = new SetExpressCheckout();
            expressCheckout.UserName = "???"; // (from step 2 above)
            expressCheckout.Password = "???"; // (from step 2 above)
            expressCheckout.Signature = "???"; // (from step 2 above)
            expressCheckout.ServerType = ServerType.Sandbox; // (API Endpoints:
            expressCheckout.SecurityMode = SecurityMode.Signature;

The rest is simply creating name=value pairs using "expressCheckout.Add()" based on which method you are calling (see link above). You call "SetExpressCheckout" first to get a token (there's a class called "SetExpressCheckout" [see example above]), then "GetExpressCheckoutDetails", then "DoExpressCheckoutPayment" (there's a class for each one). TIP: You can skip "GetExpressCheckoutDetails" if you don't need any details (such as shipping) by appending "&useraction=commit" to the URL you use to redirect the customer (example: "‑checkout&useraction=commit&token=").

I hope I made someone's life a little easier. ;)