plus api如何获取iOS的UNAuthorizationStatus枚举

let UNUserNotificationCenter = plus.ios.import("UNUserNotificationCenter");
let center = UNUserNotificationCenter.currentNotificationCenter();
let settings = plus.ios.invoke( center, 'notificationSettings');
let authorizationStatus = plus.ios.getAttribute(settings,'authorizationStatus')

上面的代码我获取到了push的授权情况，要与UNAuthorizationStatus的枚举比较，怎么写这个比较了