iOS - 無法從switch語句跳轉到此case標簽？

Question

我正在嘗試在成功進行應用購買交易時將數據發布到我的數據庫。 也就是說，當我使用下面的代碼時，XCode會拋出錯誤：

“無法從switch語句跳轉到此案例標簽”

我怎樣才能解決這個問題？ 見下面的代碼。

.M

- (void)paymentQueue:(SKPaymentQueue *)queue updatedTransactions:(NSArray *)transactions{
    for(SKPaymentTransaction *transaction in transactions){
        switch(transaction.transactionState){
            case SKPaymentTransactionStatePurchasing: NSLog(@"Transaction state -> Purchasing");

                break;
            case SKPaymentTransactionStatePurchased:


                self.indicatorThree.hidden = YES;
                [self.indicatorThree stopAnimating];

                self.indicatorTwo.hidden = YES;
                [self.indicatorTwo stopAnimating];

                self.indicatorThree.hidden = YES;
                [self.indicatorThree stopAnimating];


                NSMutableDictionary *viewParams3 = [NSMutableDictionary new];
                [viewParams3 setValue:@"current_user" forKey:@"view_name"];
                [DIOSView viewGet:viewParams3 success:^(AFHTTPRequestOperation *operation, id responseObject) {

                    self.currentUser = [responseObject mutableCopy];

                    NSString *pointBalance = self.currentUser[0][@"points balance"];



                    NSMutableDictionary *userData = [NSMutableDictionary new];


                    int result = [pointBalance intValue] + [self.pointsPurchase intValue];
                    NSLog(@"THIS IS THE RESULT POINTS NUMBER %d", result);

                    NSString *resultPoints = [NSString stringWithFormat:@"%d", result];


                    NSDictionary *targetPoints = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects: resultPoints, nil] forKeys:[NSArray arrayWithObjects:@"value", nil]];
                    NSDictionary *finalPoints = [NSDictionary dictionaryWithObject:[NSArray arrayWithObject:targetPoints] forKey:@"und"];

                    [userData setObject:finalPoints forKey:@"field_points_balance"];

                    NSLog(@"FINAL POINTS TO POST %@", finalPoints);

                    NSDictionary *user = [[DIOSSession sharedSession] user];
                    NSString *uid = user[@"uid"];


                    [userData setObject:uid forKey:@"uid"];

                    [DIOSUser
                     userUpdate:userData
                     success:^(AFHTTPRequestOperation *op, id response) { /* Handle successful operation here */

                         NSString *userPoints = user[@"field_points_balance"][@"und"][0][@"value"];
                         NSLog(@"AFTER SAVE USER POINTS %@", userPoints);



                         [[NSNotificationCenter defaultCenter] postNotificationName:@"loginComplete" object:nil];


                     }
                     failure:^(AFHTTPRequestOperation *op, NSError *err) { /* Handle operation failire here */

                         NSLog(@"User data failed to update!");
                     }
                     ];



                } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
                    NSLog(@"Failure: %@", [error localizedDescription]);
                }];


                [[SKPaymentQueue defaultQueue] finishTransaction:transaction];
                NSLog(@"Transaction state -> Purchased");
                break;
            case SKPaymentTransactionStateRestored:
                NSLog(@"Transaction state -> Restored");

                [[SKPaymentQueue defaultQueue] finishTransaction:transaction];
                break;
            case SKPaymentTransactionStateFailed:

                if(transaction.error.code == SKErrorPaymentCancelled){
                    NSLog(@"Transaction state -> Cancelled");
                    //the user cancelled the payment ;(
                }
                [[SKPaymentQueue defaultQueue] finishTransaction:transaction];
                break;
        }
    }
}

Answer 1

我之前遇到過同樣的問題，只需在你的情況下添加{}，你的所有問題都將得到解決。

塊定義創建了一個新的作用域，它似乎會干擾編譯器正確解釋switch語句的能力。

為每個案例標簽添加范圍分隔符可解決錯誤。 我認為這是因為塊的范圍現在毫無疑問是案例范圍的子項。

switch (transaction.transactionState) {
    case 0:
    {
        // ...
        break;
    }
    case 1:
    {
        // ...
        break;
    }
    default:
        break;
}