在尝试同时支持iOS8和更低版本时，我并没有像Kevin建议的那样使用isregisteredforremotenotifations。相反，我使用了currentUserNotificationSettings，它在我的测试中工作得很好。

+ (BOOL)notificationServicesEnabled {
    BOOL isEnabled = NO;

    if ([[UIApplication sharedApplication] respondsToSelector:@selector(currentUserNotificationSettings)]){
        UIUserNotificationSettings *notificationSettings = [[UIApplication sharedApplication] currentUserNotificationSettings];

        if (!notificationSettings || (notificationSettings.types == UIUserNotificationTypeNone)) {
            isEnabled = NO;
        } else {
            isEnabled = YES;
        }
    } else {
        UIRemoteNotificationType types = [[UIApplication sharedApplication] enabledRemoteNotificationTypes];
        if (types & UIRemoteNotificationTypeAlert) {
            isEnabled = YES;
        } else{
            isEnabled = NO;
        }
    }

    return isEnabled;
}

这个Swifty解决方案对我来说效果很好(iOS8+)，

方法:

func isNotificationEnabled(completion:@escaping (_ enabled:Bool)->()){
    if #available(iOS 10.0, *) {
        UNUserNotificationCenter.current().getNotificationSettings(completionHandler: { (settings: UNNotificationSettings) in
            let status =  (settings.authorizationStatus == .authorized)
            completion(status)
        })
    } else {
        if let status = UIApplication.shared.currentUserNotificationSettings?.types{
            let status = status.rawValue != UIUserNotificationType(rawValue: 0).rawValue
            completion(status)
        }else{
            completion(false)
        }
    }
}

用法:

isNotificationEnabled { (isEnabled) in
            if isEnabled{
                print("Push notification enabled")
            }else{
                print("Push notification not enabled")
            }
        }

Ref

iOS8+ (OBJECTIVE C)

#import <UserNotifications/UserNotifications.h>


[[UNUserNotificationCenter currentNotificationCenter]getNotificationSettingsWithCompletionHandler:^(UNNotificationSettings * _Nonnull settings) {

    switch (settings.authorizationStatus) {
          case UNAuthorizationStatusNotDetermined:{

            break;
        }
        case UNAuthorizationStatusDenied:{

            break;
        }
        case UNAuthorizationStatusAuthorized:{

            break;
        }
        default:
            break;
    }
}];

在iOS7和之前，你应该使用enabledRemoteNotificationTypes并检查它是否等于(或不等于取决于你想要什么)UIRemoteNotificationTypeNone。

然而，对于iOS8来说，仅仅检查isregisteredforremotenotifations并不总是足够的，因为上面有许多状态。你还应该检查application.currentUserNotificationSettings.types是否等于(或不等于取决于你想要什么)UIUserNotificationTypeNone!

isregisteredforremotenotifations可能返回true，即使currentUserNotificationSettings。types返回UIUserNotificationTypeNone。

在Xamarin，以上所有的解决方案都不适合我。 这是我用的:

public static bool IsRemoteNotificationsEnabled() {
    return UIApplication.SharedApplication.CurrentUserNotificationSettings.Types != UIUserNotificationType.None;
}

当你在设置中更改通知状态后，它也会得到实时更新。

我尝试使用@Shaheen ghassy提供的解决方案支持iOS 10及以上版本，但发现剥夺问题enabledRemoteNotificationTypes。所以，我找到的解决方案是使用isregisteredforremotenotification而不是enabledRemoteNotificationTypes，这在iOS 8中已弃用。下面是我最新的解决方案，对我来说非常有效:

- (BOOL)notificationServicesEnabled {
    BOOL isEnabled = NO;
    if ([[UIApplication sharedApplication] respondsToSelector:@selector(currentUserNotificationSettings)]){
        UIUserNotificationSettings *notificationSettings = [[UIApplication sharedApplication] currentUserNotificationSettings];

        if (!notificationSettings || (notificationSettings.types == UIUserNotificationTypeNone)) {
            isEnabled = NO;
        } else {
            isEnabled = YES;
        }
    } else {

        if ([[UIApplication sharedApplication] isRegisteredForRemoteNotifications]) {
            isEnabled = YES;
        } else{
            isEnabled = NO;
        }
    }
    return isEnabled;
}

我们可以很容易地调用这个函数，访问它的Bool值，并将其转换为字符串值:

NSString *str = [self notificationServicesEnabled] ? @"YES" : @"NO";

希望它也能帮助到其他人:) 快乐的编码。