NSUserDefaults.Notifications.ObserveDidChange 方法
定义
重要
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重载
ObserveDidChange(EventHandler<NSNotificationEventArgs>) |
常量的强类型通知 DidChangeNotification 。 |
ObserveDidChange(NSObject, EventHandler<NSNotificationEventArgs>) |
常量的强类型通知 DidChangeNotification 。 |
ObserveDidChange(EventHandler<NSNotificationEventArgs>)
常量的强类型通知 DidChangeNotification 。
public static Foundation.NSObject ObserveDidChange (EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveDidChange : EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject
参数
- handler
- EventHandler<NSNotificationEventArgs>
发布通知时调用的方法。
返回
令牌对象,可用于通过释放通知或将其传递给来停止接收通知 RemoveObservers(IEnumerable<NSObject>)
注解
此方法可用于订阅 DidChangeNotification 通知。
// Listen to all notifications posted for any object
var token = NSUserDefaults.Notifications.ObserveDidChange ((notification) => {
Console.WriteLine ("Observed DidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = NSUserDefaults.Notifications.ObserveDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed DidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();
适用于
ObserveDidChange(NSObject, EventHandler<NSNotificationEventArgs>)
常量的强类型通知 DidChangeNotification 。
public static Foundation.NSObject ObserveDidChange (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveDidChange : Foundation.NSObject * EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject
参数
- objectToObserve
- NSObject
要观察的对象。
- handler
- EventHandler<NSNotificationEventArgs>
发布通知时调用的方法。
返回
令牌对象,可用于通过释放通知或将其传递给来停止接收通知 RemoveObservers(IEnumerable<NSObject>)
注解
此方法可用于订阅 DidChangeNotification 通知。
// Listen to all notifications posted for any object
var token = NSUserDefaults.Notifications.ObserveDidChange ((notification) => {
Console.WriteLine ("Observed DidChangeNotification!");
};
// Listen to all notifications posted for a single object
var token = NSUserDefaults.Notifications.ObserveDidChange (objectToObserve, (notification) => {
Console.WriteLine ($"Observed DidChangeNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();