Using JSON sessions and foreach() statements - php

Question

I've stumbled upon some problems while creating a shopping application. In short:
I'm using a php $_SESSION['cart'] to register all the products inside the cart
The products are registered and added to the cart by the following code:
else {// It's new: Add it to the array
$_SESSION['cart']['cartItems'][] = $cartProduct;
$_SESSION['cart']['totalItems']++;
}
To that function a cart with 2 or more products looks like this:
{"cartItems":[{
"id":"3",
"name":"Bedrukte Jurk",
"price":25.99,
"size":"L",
"quantity":"12",
"total_product_price":311.88
},
{
"id":"11",
"name":"Product voorraad id",
"price":144,
"size":"M",
"quantity":"23",
"total_product_price":3312
}
],
"totalPrice":3623.88,
"totalItems":2
}
So now i've got two questions regarding my $_SESSION['cart'];
How would i be able to delete a specific product. I was thinking about using the product id. And for now that has been working for me unless the unset($_SESSION['cart']['cartItems'] ... id part that i still haven't figured out. So how would i be able to tell php to delete the row with the requested id.
The second question is a bit more confusing to me since this has to do with writing the "cart" to the database on "payOrder" click.
So i've been struggling with this part and i've tried using a foreach() statement to get each row. But sadly only the first product is written in the database. The function handeling this foreach() is shown down below:
$cart_encode = json_encode($_SESSION['cart']['cartItems']);
$cartDecode = json_decode($cart_encode);
$date = date("Y-m-d h:i:s");
// Create the cart Using XML
$opt = $webService->get(array(
'resource' => 'carts',
));
// Define the $resource
$resource = $opt->children()->children();
// Adding the product items
foreach ($cartDecode as $key => $cartItem) {
$resource->associations->cart_rows->cart_row->id_product = $cartItem->{"id"};
$resource->associations->cart_rows->cart_row->id_product_attribute = 1;
$resource->associations->cart_rows->cart_row->id_address_delivery = 1;
$resource->associations->cart_rows->cart_row->quantity = $cartItem->{"quantity"};
}
Update after the comments
So as #Randall has mentioned it's better to use the product_id's as a new array index layer for deleting the row's in the cart, in this case a particulair product.
So i've edited my code to an older state in wich this is true and Question one is solved.
Anyhow the new JSON structure is:
{"cartItems": {
"5": {
"id":"5",
"name":"Bedrukte Zomerjurk",
"price":30.5,
"size":"L",
"quantity":"34",
"total_product_price":1037
},
"4": {
"id":"4",
"name":"Bedrukte Avond Jurk",
"price":50.99,
"size":"L",
"quantity":"3",
"total_product_price":152.97
}
},
"totalPrice":1189.97,
"totalItems":2
}
Still Question 2 sadly stays unanswered about the database input. I hope there are some people that could help me out.
PS: #Randall thanks for the "it makes no difference tip, it solved question 1 of the 2!".
I hope my question is clear and if it isn't please let me know.
As always,
Thanks in advance!