Update all Items

[rasselll]

Hi, I have a button for update but how can I update all items not just one?

// Update item
if (isset($_POST['update'])) {

	$cart->update($_POST['id'], $_POST['qty'], [
		'price' => $_POST['price'],
		'color' => (isset($_POST['color'])) ? $_POST['color'] : '',
		'size' => (isset($_POST['size'])) ? $_POST['size'] : '',
	]);
}