//------------------- type details -------------------
        public ActionResult ProductTypeDetails(int?id)  // id = type id
        {
            if (id == null)
            {
                return(new HttpStatusCodeResult(HttpStatusCode.BadRequest));
            }

            ViewData["product"] = DAL.filterProductsByType(id);

            ProductType productType = DAL.GetProductTypeByID(id);

            if (productType != null)
            {
                return(View(productType));
            }
            else
            {
                return(View("~/Views/Shared/Error.cshtml"));
            }
        }