public async Task <bool> AddProductToStoreAsync(string storeName, string productName) { StoresEntity stores = await context.Stores.FirstOrDefaultAsync(s => s.Name == storeName); if (stores == null) { throw new NoExistInDbException(ExceptionMessages.CannotAddProductToStoreSTORE()); } ProductsEntity products = await context.Products.FirstOrDefaultAsync(p => p.Name == productName); if (products == null) { throw new NoExistInDbException(ExceptionMessages.CannotAddProductToStorePRODUCT()); } stores.StoreProduct = new List <ProductsAndStoresEntity>(); stores.StoreProduct.Add(new ProductsAndStoresEntity { ProductId = products.Id }); try { return((await context.SaveChangesAsync()) > 0); } catch (DbUpdateException dbe) { throw new ExistsInDBException(ExceptionMessages.CannotAddProductToStore(), dbe); } }