public Collection<Category> Categorues()
        {
            var result = new Collection<Category>();
            var c1 = new Category();
            c1.Name = "Pants";
            c1.Products = new Collection<Product>();

            var c1p1 = new Product();
            c1p1.Name = "Yellow pants";
            c1p1.Price = 12;

            var c1p2 = new Product();
            c1p2.Name = "Blue pants";
            c1p2.Price = 13;

            c1.Products.Add(c1p1);
            c1.Products.Add(c1p2);

            var c2 = new Category();
            c2.Name = "T-shirts";
            c2.Products = new Collection<Product>();

            var c2p1 = new Product();
            c2p1.Name = "White t-shirt";
            c2p1.Price = 12;

            var c2p2 = new Product();
            c2p2.Name = "Black t-shirt";
            c2p2.Price = 13;

            c2.Products.Add(c2p1);
            c2.Products.Add(c2p2);

            result.Add(c1);
            result.Add(c2);

            return result;
        }
        protected void AddNew_Command(object sender, CommandEventArgs e)
        {

            var parent = this.AddNewCategoryForm.FindControl("AddNewTextBox");
            var textbox = parent as TextBox;
            string text = textbox.Text;

            if (string.IsNullOrWhiteSpace(text))
            {
                ErrorSuccessNotifier.AddErrorMessage("Category name must not be emty.");
                ErrorSuccessNotifier.ShowAfterRedirect = true;
                RedirectHome();
            }
            else if (text.Length > 100)
            {
                ErrorSuccessNotifier.AddErrorMessage("Category name is too long.");
                ErrorSuccessNotifier.ShowAfterRedirect = true;
                RedirectHome();
            }
            else
            {
                var context = new ApplicationDbContext();
                var newCat = new Category()
                {
                    Name = text
                };

                context.Categories.Add(newCat);
                context.SaveChanges();

                ErrorSuccessNotifier.AddSuccessMessage("Category created.");
                ErrorSuccessNotifier.ShowAfterRedirect = true;
                RedirectHome();
            }
        }