protected void AddOrderToDB(CartItem ci, int order_code)
        {
            UthDataContext db    = new UthDataContext();
            UthOrder       order = new UthOrder();

            //get current user
            order.cust_id       = db.UthCustomers.Single(c => c.cust_mail.Equals(User.Identity.Name)).cust_id;
            order.ord_code      = order_code;
            order.ord_date      = DateTime.Now;
            order.ord_delivered = false;
            order.ord_quantity  = ci.Quantity;
            order.prod_id       = ci.ProductId;

            db.UthOrders.InsertOnSubmit(order);

            UthProduct product = db.UthProducts.Single(p => p.prod_id == ci.ProductId);

            //substract <quantity> units from stock for this product
            //we can't have negative values in stock!
            int tempstock = product.prod_stock - order.ord_quantity;

            if (product.prod_stock > 0 && tempstock > 0)
            {
                product.prod_stock = tempstock;
            }

            //write changes
            db.SubmitChanges();
        }
        protected void btnRegister_Click(object sender, EventArgs e)
        {
            if (this.IsValid)
            {
                UthDataContext db = new UthDataContext();
                var            v  = db.UthCustomers.Where(cust => cust.cust_mail.Equals(tbEmail.Text));

                if (v.Count() == 0)
                {
                    UthCustomer c = new UthCustomer();

                    //c.cust_country =tbCountry.Text;
                    c.cust_country_code = int.Parse(ddlCountry.SelectedItem.Value);
                    c.cust_mail         = tbEmail.Text;
                    c.cust_name         = tbName.Text;
                    c.cust_password     = tbPassword.Text;
                    c.cust_phone        = tbPhone.Text;
                    c.cust_postalcode   = int.Parse(tbPostal.Text);
                    c.cust_streetname   = tbStreet.Text;
                    c.cust_streetnumber = int.Parse(tbHouse.Text);
                    c.cust_city         = tbCity.Text;

                    db.UthCustomers.InsertOnSubmit(c);
                    db.SubmitChanges();

                    bool authenticated = Customer.AuthenticateCustomer(c.cust_mail, c.cust_password);
                    if (authenticated)
                    {
                        FormsAuthentication.RedirectFromLoginPage(c.cust_mail, false);
                    }
                    Response.Redirect("~/ThankYou.aspx");
                }

                pError.Visible = true;
            }
        }