pfSense

/*

 * converts a string like "a,b,c,d"

 * into an array like array("a" => "b", "c" => "d")

 */

function explode_assoc($delimiter, $string) {

	$array = explode($delimiter, $string);

	$result = array();

	$numkeys = floor(count($array) / 2);

	for ($i = 0; $i < $numkeys; $i += 1) {

		$result[$array[$i * 2]] = $array[$i * 2 + 1];

	}

	return $result;

}