services.AddDbContext<ApplicationDbContext>(options =>
                options.UseSqlServer(
                    Configuration.GetConnectionString("DefaultConnection")));

            services.AddScoped(typeof(IUnitOfWork), typeof(UnitOfWork));

 public class Product
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public int BrandId { get; set; }
        public Brand Brand { get; set; }
    }

 public class Brand
    {
          public int Id { get; set; }
        public string Name { get; set; }

        public List<Product> Products { get; set; }
    }

private readonly IUnitOfWork _unitOfWork;

 public class ProductController : Controller
    {
        private readonly IUnitOfWork _unitOfWork;

        public ProductController(IUnitOfWork unitOfWork)
        {
            _unitOfWork = unitOfWork;
        }

        public IActionResult BrandIndex()
        {
            var model = _unitOfWork.Repository<Brand>().GetAllInclude(x => x.Products);
            //do something if you want

            return View(model);
        }

        public IActionResult AddBrand()
        {

            return View();
        }

        [HttpPost]
        public IActionResult AddBrand(Brand model)
        {
            if (!ModelState.IsValid)
            {
                ModelState.AddModelError("", "Something wrong");
                return View(model);
            }

            _unitOfWork.Repository<Brand>().Insert(model);
            //save new data to database
            _unitOfWork.Commit();
            return RedirectToAction("BrandIndex");
        }

        public IActionResult AddProduct()
        {
            var model=new Product();
            //brand list for dropdown
            var dbBrand = _unitOfWork.Repository<Brand>().GetAll();

            ViewBag.BrandList = dbBrand.Select(x => new SelectListItem
            {
                Text = x.Name,
                Value = x.Id.ToString()
            });
            return View(model);
        }



        [HttpPost]
        public async Task<IActionResult> AddProduct(Product product)
        {
            if (!ModelState.IsValid)
            {
                ModelState.AddModelError("","Something wrong");
                return View(product);
            }

            _unitOfWork.Repository<Product>().Insert(product);
            //save asynchronously to database
            await _unitOfWork.CommitAsync();
            return RedirectToAction("ProductList");
        }


        public IActionResult ProductList()
        {
            var model = _unitOfWork.Repository<Product>().GetAllInclude(x => x.Brand);

            return View(model);
        }
    }