Implementation of simple Paypal Express Checkout in PHP.

PayPal allows their users to implement checkout functions using their API. But implementing the full API is not a piece of cake. There are some libraries on the web, but the most of them are paid, closed or too complex.

If you wanna implement simple and single-item payments (i.e. "pay for service" or "pay for source code"), you can use my, free and open, library described here.

This library was written as a part of my framework, but it's usable standalone too, I hope. ;)

Using is as easy as

$r = new PayPal();
$r->doExpressCheckout(10, 'Da Greatest Library You Ever Seen');

and

$final = $r->doPayment();

if ($final['ACK'] == 'Success') {
	echo 'Succeed!';
} else {
	echo 'Error!';
}

More information and step-by-step manual at PHP Suit