Elegant Solution for Array Session - Ecommerce Basket

[eluser]Yorkshire Pudding[/eluser]
Hi all,

I'm currently rebuilding one of my sites for the first time using Codeignitor.

My current basket code uses arrays saved in a session.

My old code looked like this

Code:

if (!isset($_SESSION['cart']))
    {
        $_SESSION['cart'] = array();
    }

    if (isset($_POST['productid']))
    {
        $_SESSION['cart'][] = $_POST['productid'];
        
    header('location: ' . $_SERVER['PHP_SELF'] . '?' . SID);
    exit();
    }

My new Codeignitor code looks like this:

Code:

if($this->input->post('product_id'))
            {
                if($this->session->userdata('cart'))
                {
                    if(!is_array($this->session->userdata('cart')))
                    {
                        $product_array = array();
                        $product_array[] = $this->session->userdata('cart');
                    }
                    else
                    {
                        $product_array = $this->session->userdata('cart');    
                    }
                    $product_array[] = $this->input->post('product_id');
                    $this->session->set_userdata('cart', $product_array);
                }
                else
                {
                    $this->session->set_userdata('cart', $this->input->post('product_id'));
                }    
            }

It works, but looks a bit bloated to me. Is there a more elegant way of doing this using Codeignitor?

Thanks for all you help in advance