public static int UpdateStock( 
   Order order 
)

class MyPage : System.Web.UI.Page
{
   private void DeleteOrders(string orderID)
   {
       Dynamicweb.eCommerce.Orders.OrderState deletedOrderState = null;

       //Check for a 'Deleted' Order state and use if exists
       Dynamicweb.eCommerce.Orders.OrderStateCollection orderStates = Dynamicweb.eCommerce.Orders.OrderState.getAllOrderstates(false);
       foreach (Dynamicweb.eCommerce.Orders.OrderState orderState in orderStates) {
           if (orderState.IsDeleted) {
               deletedOrderState = orderState;
           }
       }

       Dynamicweb.eCommerce.Orders.Order order = Dynamicweb.eCommerce.Orders.Order.Create(orderID);
       order.Deleted = true;
       order.StateID = deletedOrderState.ID;
       order.Save();

       if (order.Complete)
       {
           Product.UpdateStock(order);
       }
   }
}