I'm confused with paypal sequences. I want to add in the website a donation paypal link "for members only" it's my client demand and I want to store in the db if the user have made a donation or not and how much. Now he is using in the website just the link https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=6SENM6TBA5EPL so this means that he have an account on paypal and have created a button with this id "6SENM6TBA5EPL". what I know is that from the button config. in paypal site we can set cancel and success links,it's ok. But I want to send the user_id and receive it back from paypal as a variable on the success link if the donation is made.
So it's just to add another url variable like https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=6SENM6TBA5EPL&user_id=123
or I can use the paypal form like this
<form action="https://www.paypal.com/cgi-bin/webscr" method="post" target="_top">
<input type="hidden" name="user_id" value="123">
<input type="hidden" name="cmd" value="_s-xclick">
<input type="hidden" name="hosted_button_id" value="6SENM6TBA5EPL">
<input type="image" src="https://www.paypalobjects.com/fr_FR/FR/i/btn/btn_donate_LG.gif" border="0" name="submit" alt="PayPal - la solution de paiement en ligne la plus simple et la plus sécurisée !">
</form>