public static async Task AddRentalAsync(string title, int quantity) { Dictionary <string, string> parameters = new Dictionary <string, string> { { "Title", title }, { "Quantity", quantity.ToString() } }; FormUrlEncodedContent encodedContent = new FormUrlEncodedContent(parameters); using (HttpResponseMessage response = await ShoppingCartController.AddRental(encodedContent)) { int status = (int)response.StatusCode; string body = await response.Content.ReadAsStringAsync(); if (status == 200) { return; } else if (status == 400) { throw new ArgumentException(body); } else if (status == 401) { throw new UnauthenticatedException(); } else if (status == 404) { throw new RentalDoesNotExistException(); } else if (status == 500) { throw new ServerException(); } else { throw new Exception("An uncaught error occurred."); } } }