<checkout_cart_save_after> /*事件名字*/                <observers>                    <deal> /*模块名字*/                        <class>deal/observer_cart</class> /*文件地址deal/Model/Observer/Cart.php*/                        <method>findRequiredOptions</method> /*方法名字*/                    </deal>                </observers></checkout_cart_save_after>

 public function findRequiredOptions(Varien_Event_Observer $observer)    {        $cart = $observer->getEvent()->getCart();        $productIds = $cart->getProductIds();        foreach($productIds as $id)        {            $product = Mage::getModel(‘catalog/product‘)->load($id);            try {                $product->getTypeInstance(true)->checkProductBuyState($product);            } catch (Mage_Core_Exception $e) {                Mage::getSingleton(‘core/session‘)->addNotice($product->getName().Mage::helper(‘sales‘)->__(‘ do not have all the required options.‘));            }        }    }