Running own's php script upon pressin Paypal buy-now button - php

Question

and thanks for the great help your community provides.
Here is a question regarding Paypal. The code below creates a buy-now non-hosted button. I would like to be able to do run my geoTestArray.php code, currently simply included, as the user presses the Buy Now button, and not when the button is displayed on the page.
Is this possible at all?
Thanks in advance,
Joe
<?php
include ('geoTestArray.php');
echo "<form action=\"https://www.paypal.com/cgi-bin/webscr\" method=\"post\">
<input type=\"hidden\" name=\"business\" value=\"shop#mysite.com\">
<input type=\"hidden\" name=\"cmd\" value=\"$cmd\">
<input type=\"hidden\" name=\"amount\" value=\"$price\">
<input type=\"hidden\" name=\"shipping\" value=\"$shipping\">
<input type=\"hidden\" name=\"currency_code\" value=\"$currency\">
<input type=\"hidden\" name=\"shipto\" value=\"$shipto\">
<input type=\"hidden\" name=\"item_name\" value=\"$title\">";
if ($cmd == 'cart') {
echo "<input type=\"hidden\" name=\"add\" value=\"1\">";
}
include('./quantities2.php');
echo "<input type=\"hidden\" name=\"lc\" value=\"US\">
<input class=\"submit\" type=\"image\" src=\"$button\" border=\"0\" name=\"submit\" alt=\"$altaction\">
<img alt=\"\" border=\"0\" src=\"https://www.paypal.com/en_US/i/scr/pixel.gif\" width=\"1\" height=\"1\">
</form>";
?>

Answer 1

You can display only a form with one input, for example item_id.
After submitting this form you search for item details, execute your geoTestArray.php in backend and after that you can redirect your users to paypal using header("location: $query");
here's how I would do:
<?php
if( isset($_POST['do_action']) && $_POST['do_action'] != "" ) {
//check for non-empty item_id field
//run your geoTestArray.php script
//get item details from database and build your paypal query
$query = "https://www.paypal.com/cgi-bin/webscr&cmd=_xclick"; // add rest of paypal request fields separated by &
header( "Location: $query" );
}
?>
<form action='' method='post'>
<input type='hidden' name='item_id' value'your_item_id'>
<input type='submit' name='do_action' value='Buy'>
<form>
Hope I helped you! :d

Answer 2

Thanks everyone for comments and solution options. I have eventually chosen to modify an onSubmit javascript I had on my page, by adding:
function InterceptForm(formObj) {
var newshipto = httpGet('geoTestArray.php');
formObj.shipto.value = newshipto;
}
The above code makes use of the httpGet() function posted in this other stackoverflow post:
HTTP GET request in JavaScript?
To complete the puzzle:
The code below is in the html in my page
<script language="javascript">
// During onLoad, loop through all forms and for each form object do something
function InterceptForm(formobj) {
formobj.onsubmit = function ff() {
interceptform(formobj);
};
}
</script>
The code below gathers all forms on the page and runs the above javascript on each (NOTE: you may want to name your forms so that you only run the script on the relevant forms and not on all forms):
<script language="javascript">
function GetForms() {
var formsCollection = document.getElementsByTagName("form");
for(var i=0;i<formsCollection.length;i++)
{
if (formsCollection[i].name != "seecart")
{
InterceptForm(formsCollection[i]);
}
}
return true;
}
</script>
The code below is the onLoad function:
<script language="javascript">
function onLoadFunction () {
GetForms();
return true;
}
</script>
Cheers,
Joe