根据 [[UIApplication sharedApplication] enabledRemoteNotificationTypes] 的返回值来进行判断，该返回值是一个枚举值，如下：

typedef enum {

UIRemoteNotificationTypeNone= 0,

UIRemoteNotificationTypeBadge= 1 << 0,

UIRemoteNotificationTypeSound= 1 << 1,

UIRemoteNotificationTypeAlert= 1 << 2,

UIRemoteNotificationTypeNewsstandContentAvailability = 1 << 3,

} UIRemoteNotificationType;

如果是 UIRemoteNotificationTypeNone ，则可以认为推送开关没有打开，反之亦然。