SetCheckout Method
Call this method to begin the Express Checkout process and fetch a token from PayPal which will encode transaction details.
Syntax
expresscheckout.setCheckout([callback])
Callback
The 'callback' parameter specifies a function which will be called when the operation completes (or an error is encountered). If the 'callback' parameter is not specified, then the method will block and will not return until the operation completes (or an error is encountered).
The callback for this method is defined as:
function(err){ }
'err' is the error that occurred. If there was no error, then 'err' is 'null'.
'err' has 2 properties which hold detailed information:
err.code err.message
Remarks
This method queries PayPal for a ResponseToken and begins the Express Checkout process. This token is used to identify the transaction on the PayPal network.
The following properties are required before calling SetCheckout:
After calling this method, you should check the Ack property to determine whether the request was successful. If so, append the ResponseToken value to the following PayPal URL, and redirect your customer there.
https://www.sandbox.paypal.com/cgi-bin/webscr?cmd=_express-checkout&token=
The customer will sign in and fill out payment details on PayPal's site. Afterwards PayPal will automatically redirect the customer back to the ReturnURL you specified, along with the updated token appended to the URL. This token should be parsed from the URL and set as the Token property. You may then proceed in calling GetCheckoutDetails and CheckoutPayment.