PHP8 Fatal error when using Cart::get_cart_id() about bigcommerce-for-wordpress

[MlKilderkin]

Hello @ll-r-magner
The $temp = new Cart(); should throw an error. It is not an issue. PHP 8.0 has more strict rules and class constructor expecting 1 argument provided.
In order to achieve what you want use next code

use BigCommerce\Cart\Cart;
use BigCommerce\Container\Api;

$container = bigcommerce()->container();
$cart_api  = $container[ Api::FACTORY ]->cart();
$cart = new Cart( $cart_api );
$cart->get_cart_id()

First you get a global container. Than you get cart api entity and only after that you will be able to use Cart class.

$cart = bigcommerce()->cart; won't work for you because it provides cart container and not a card itself.

Please let me know if this helps or you have additional question

[ll-r-magner]

Fatal error: Uncaught ArgumentCountError: Too few arguments to function BigCommerce\Cart\Cart::__construct(), 0 passed in /www/ledgeclone121222_223/public/wp-content/themes/ll-ecommerce/page-templates/ll-umbrellas-pdp.php on line 317 and exactly 1 expected in /www/ledgeclone121222_223/public/wp-content/plugins/bigcommerce/src/BigCommerce/Cart/Cart.php:34 Stack trace: #0 /www/ledgeclone121222_223/public/wp-content/themes/ll-ecommerce/page-templates/ll-umbrellas-pdp.php(317): BigCommerce\Cart\Cart->__construct() #1 /www/ledgeclone121222_223/public/wp-includes/template.php(783): require_once('/www/ledgeclone...') #2 /www/ledgeclone121222_223/public/wp-content/themes/ll-ecommerce/bigcommerce/single-bigcommerce_product.php(48): load_template('/www/ledgeclone...') #3 /www/ledgeclone121222_223/public/wp-includes/template-loader.php(106): include('/www/ledgeclone...') #4 /www/ledgeclone121222_223/public/wp-blog-header.php(19): require_once('/www/ledgeclone...') #5 /www/ledgeclone121222_223/public/index.php(17): require('/www/ledgeclone...') #6 {main} thrown in /www/ledgeclone121222_223/public/wp-content/plugins/bigcommerce/src/BigCommerce/Cart/Cart.php on line 34
There has been a critical error on this website.

[ll-r-magner]

Also have tried syntax $cart = bigcommerce()->cart; then calling it via $bc_cart_id = $cart->get_cart_id();

[ll-r-magner]

@MlKilderkin sorry im late to this been super busy. So that code works to create a new cart correct? What if a cart already exists and im just trying to add a new item to cart?

[MlKilderkin]

Hello @ll-r-magner no problem. Code above creates an object that allows to retrieve card id stored in cookies.

[ll-r-magner]

@MlKilderkin Ok, while I was waiting for a reply just now I think I was able to get it. If you dont mind checking out what im doing here. The "add_to_cart" function was created by another dev which I can share if need be. Our products are a little over engineered so some extra logic is required. As far as dealing with the Cart() object does this look right?

UPDATE: Well adding this product to cart didnt throw a PHP error so thats progress. I am getting a 400 response when adding to cart though.

UPDATE V2: So, because the add_to_cart function relies on redirecting to the cart page it does work as intended however, we use the BC4WP setting AJAX Add to Cart which doesn't redirect. Is there a way to make certain template files redirect while allowing the majority to use the global setting? @MlKilderkin

	if (!empty($_POST)) {
		// cart id from bigcommerce cookie
    $container = bigcommerce()->container();
    $cart_api  = $container[ Api::FACTORY ]->cart();
    $cart = new Cart( $cart_api );
    $bc_cart_id = $cart->get_cart_id();
    // $cart->get_cart_id()
    // $cart = bigcommerce()->cart;
		// $bc_cart_id = $cart->get_cart_id();

		$post_product = \BigCommerce\Post_Types\Product\Product::by_product_id( $_POST['product'] );

		if (isset($bc_cart_id) && $bc_cart_id !== '') {
			// cart has been created already
			add_to_cart($post_product, $_POST, $bc_cart_id);
			header('Location: /cart');

		} else {
			// cart has not been created
      $container = bigcommerce()->container();
      $cart_api  = $container[ Api::FACTORY ]->cart();
      $cart = new Cart( $cart_api );
      // $cart->get_cart_id();

			$new_cart = add_to_cart($post_product, $_POST, null);
			$cart->set_cart_id($new_cart['data']['id']);

			header('Location: /cart');
		}
	}

[ll-r-magner]

@MlKilderkin Is there a way to set a single page to redirect to /cart on add to cart and have the rest of the pages do the AJAX add to cart function (not redirecting to cart)?