public CompositeSubcategoryViewModel GetNewSubcategoryViewModelWithCategories()
        {
            CompositeSubcategoryViewModel model = new CompositeSubcategoryViewModel();

              using (var context = new WebShopMVCContext())
              {
                  model.Categories = context.Categories.Select(c => new CategoryViewModel
                  { CategoryName = c.CategoryName, CategoryId = c.CategoryId }).ToList();

              }
              return model;
        }
        public CompositeSubcategoryViewModel GetModelById(int id)
        {
            CompositeSubcategoryViewModel model;

            using (var context = new WebShopMVCContext())
            {
                var subcategory = context.Subcategories.Find(id);
                model = new CompositeSubcategoryViewModel
                {
                    CategoryId = subcategory.CategoryId,
                    SubcategoryId = subcategory.SubcategoryId,
                    SubcategoryName = subcategory.SubcategoryName,
                    Categories = context.Categories.Select(c => new CategoryViewModel
                        { CategoryName = c.CategoryName, CategoryId = c.CategoryId }).ToList()
                };

            }
            return model;
        }