我想在 Apple Pay 上设置传递变量，我将其设置NSDictionary为JSON数据，例如：
PKPaymentRequest *request = [[PKPaymentRequest alloc] init];
[request setApplicationData:[NSJSONSerialization dataWithJSONObject:@{@"name":@"USER_NAME"} options:NSJSONWritingPrettyPrinted error:nil]];
现在里面：
- (void)paymentAuthorizationViewController:(PKPaymentAuthorizationViewController *)controller didAuthorizePayment:(PKPayment *)payment completion:(void (^)(PKPaymentAuthorizationStatus status))completion;
我能够访问 applicationData 作为
NSError* jsonError;
NSDictionary* dataDict = [NSJSONSerialization JSONObjectWithData:payment.token.paymentData options:kNilOptions error:&jsonError];
dataDict[@"header"][@"applicationData"]包含应用程序数据
但是数据是编码的，我想@{@"name":@"USER_NAME"}从 applicationData 中获取。