How to add an array to a cookie in PHP? - php

Question

I am trying to store array to cookie. I am storing my array products item in cookie array, but it throws error.
$products = array();
$item = array($id => $name);
print_r($item);
$products[] = $item;
setcookie('products',json_encode($products),strtotime( '+1 day' ));
var_dump($_COOKIE['products']);
The above code prints
Array (
[4] => Rug Rat ) Notice: Undefined index: products in
D:\xampp\htdocs\projects\includes\classes\products.php
on line 43 NULL

Answer 1

Cookies are set when the response is sent to the client. This means that you won't be able to access them from PHP code until the next request. See the documentation for setcookie() function, section Common Pitfalls:
Cookies will not become visible until the next loading of a page that the cookie should be visible for. To test if a cookie was successfully set, check for the cookie on a next loading page before the cookie expires. Expire time is set via the expire parameter. A nice way to debug the existence of cookies is by simply calling print_r($_COOKIE);.
http://php.net/manual/en/function.setcookie.php
So, unless you echo anything, or do anything else that causes the response headers to be sent, you should see var_dumped cookie content after you refresh the page. In your code, there's print_r($item); before setcookie() is called, so you're probably getting a headers already sent warning, and the cookie is never set.
One way or another, it's rarely safe to assume that an array index is set, especially in a superglobal, like $_GET, $_POST, $_COOKIE, etc. You should always check with isset() or array_key_exists if the index is really set.