Question

All,
I’ve created a whole bunch of session variables based on an id. So for example I can have the following variables:

$_SESSION['test_variable_1'];
$_SESSION['test_variable_2'];
$_SESSION['test_variable_3'];

I’d like to read all of these with PHP and basically return a JSON array of the id at the end of the variable. So I’d like 1, 2 and 3 returned in this example. The session variables I wnat to look at will always start with test_variable_ and followed by the ID I want to obtain. What is the best way to do this?

Thanks!

Answer 1

While the better idea would’ve been to just create a sub-array within the session superglobal, so that you could use $_SESSION['test_variable'][1] and the like, you can use something like preg_grep to scan for these keys:

$keys = array_keys($_SESSION);
$matches = preg_grep('/^test_variable_\d+$/', $keys);

foreach($matches as $key) {
   $digit = substr($key, 13); // extract the digit.
   echo $_SESSION[$key];
}