Errors with json_decode, array and foreach

Question

I use this code for Virtuemart:

$product_id_to_remove = 3;
$cart = json_decode($_SESSION['__vm']['vmcart']);
foreach($cart->cartProductsData as $k => $v){
  if($v->virtuemart_product_id == $product_id_to_remove) unset($cart->cartProductsData[$k]);
}
$_SESSION['__vm']['vmcart'] = json_encode($cart);

but I get the fatal error: Cannot use object of type stdClass as array in ... line 4. If I add true at json_decode($_SESSION['__vm']['vmcart']) I get the warning: Invalid argument supplied for foreach().

How to resolve the problem?

p.s. I'm beginner in php and don't know json_ at all. The code is suggested by the link: stackoverflow.com/questions/28691203/how-to-remove-a-single-product-from-mod-virtuemart-cart

If you use `true` for the 2nd parameter, you need to refer to `$cart['cartProductsData']` as it returns an associative array rather than class. — Phylogenesis, Mar 06 '15 at 09:42
Try `foreach(get_object_vars($cart->cartProductsData) as $k => $v)` — n-dru, Mar 06 '15 at 09:45
Warning: get_object_vars() expects parameter 1 to be object, null given in — user3892905, Mar 06 '15 at 09:47
Do `var_dump($cart);` to see if there is key like 'cartProductsData' — n-dru, Mar 06 '15 at 09:56
`object(stdClass)#454 (27) { ["cartProductsData"]=> object(stdClass)#447 (2) { ["1"]=> object(stdClass)#458 (3) ...` — user3892905, Mar 06 '15 at 09:58
sorry but I don't know Virtuemart, i just want to know the value of this: `print_r($_SESSION['__vm']['vmcart'])` — Vainglory07, Mar 06 '15 at 10:00
I think your array gets confused. Can you do `print_r($cart);`? I find that easier to read than `var_dump()` — RST, Mar 06 '15 at 10:23
`stdClass Object ( [cartProductsData] => stdClass Object ( [1] => stdClass Object ( [virtuemart_product_id] => 3 [quantity] => 1 [customProductData] => Array ( ) ) [2] => stdClass Object ( [virtuemart_product_id] => 2 ...` — user3892905, Mar 06 '15 at 10:31

score 1 · Accepted Answer · answered Mar 06 '15 at 10:48

1

$cart->cartProductsData behaves like an array but it's actually an object

try this: change

unset($cart->cartProductsData[$k])

to

unset($cart->cartProductsData->$k)

answered Mar 06 '15 at 10:48

RST

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Unfortunately there is one problem: if I replace [$k] to ->$k, the product is being removed but after a while isn't, so I replace back ->$k to [$k] and removing works again but after a while I get stdClass' error, then I replace [$k] to ->$k again and the circle closes – user3892905 Mar 09 '15 at 10:11
1

This is probably due to having one or more products in cart. Add a check to see if it is just one object or an array of objects. – RST Mar 09 '15 at 12:07
Thanks, but I don't know php so well. Can you write conditions for each case? – user3892905 Mar 09 '15 at 17:21
Research a little, you want to learn, right? Otherwise I will have to send you an invoice, so I can do the work for you. Search for is_object/is_array. – RST Mar 09 '15 at 23:12

Errors with json_decode, array and foreach

1 Answers1