public void Create(ProductViewModel productViewModel) { var product = new Product() { Name = productViewModel.Name, ProviderPrice = productViewModel.ProviderPrice, State = productViewModel.State, StorePrice = productViewModel.StorePrice, VendorCode = productViewModel.VendorCode, Count = productViewModel.Count, Description = productViewModel.Description }; if (!_categoriesService.EntityExist(productViewModel.Category)) { throw new EntityNotFoundException(nameof(productViewModel.Category), productViewModel.Category.Id); } var category = _categoriesService.GetEntityById(productViewModel.Category.Id); if (!_manufacturesManager.EntityExist(productViewModel.Manufacture)) { throw new EntityNotFoundException(nameof(productViewModel.Manufacture), productViewModel.Manufacture.Id); } var manufacture = _manufacturesManager.GetEntityById(productViewModel.Manufacture.Id); if (!_providersManager.EntityExist(productViewModel.Provider)) { throw new EntityNotFoundException(nameof(productViewModel.Provider), productViewModel.Provider.Id); } var provider = _providersManager.GetEntityById(productViewModel.Provider.Id); product.Category = category; product.Manufacture = manufacture; product.Provider = provider; product.State = ProductState.Awaiting; _productsService.CreateEntity(product); }