public IActionResult OnGet()
        {
            ViewData["MaterialID"] = new SelectList(_context.Set <Material>(), "ID", "MaterialType");

            var jewelry = new Jewelry();

            jewelry.JewelryCategories = new List <JewelryCategory>();
            PopulateAssignedCategoryData(_context, jewelry);


            return(Page());
        }
        public async Task <IActionResult> OnGetAsync(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            Jewelry = await _context.Jewelry
                      .Include(b => b.Material)
                      .Include(b => b.JewelryCategories).ThenInclude(b => b.Category)
                      .AsNoTracking()
                      .FirstOrDefaultAsync(m => m.ID == id);


            if (Jewelry == null)
            {
                return(NotFound());
            }

            PopulateAssignedCategoryData(_context, Jewelry);

            ViewData["MaterialID"] = new SelectList(_context.Set <Material>(), "ID", "MaterialType");
            return(Page());
        }