How to check item in session?

Question

Yii

There is a product "Box", it may include a different composition and in a different sequence.
It is necessary to recalculate the basket when adding to the basket (session).
If the composition and sequence match, then add the quantity, and if not, then create a new element.
Please tell me how to properly structure the session so that it is more convenient to check.

Answer 1

Store boxes as arrays and then compare:

if ($a === $b){
// коробки идентичны
}

Answer 2

$session = Yii::$app->session;
$in = $seession->get('some_id');
if($in == $new){
echo 'товары одинаковые';
}