UITextView.Notifications.ObserveTextDidBeginEditing 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
多載
ObserveTextDidBeginEditing(EventHandler<NSNotificationEventArgs>)
常數的 TextDidBeginEditingNotification 強型別通知。
public static Foundation.NSObject ObserveTextDidBeginEditing (EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveTextDidBeginEditing : EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject
參數
- handler
- EventHandler<NSNotificationEventArgs>
張貼通知時叫用的方法。
傳回
權杖物件,可用來停止接收通知,方法是處置通知或傳遞至 RemoveObservers(IEnumerable<NSObject>)
備註
下列範例示範如何在程式碼中使用此方法
//
// Lambda style
//
// listening
notification = UITextView.Notifications.ObserveTextDidBeginEditing ((sender, args) => {
/* Access strongly typed args */
Console.WriteLine ("Notification: {0}", args.Notification);
});
// To stop listening:
notification.Dispose ();
//
//Method style
//
NSObject notification;
void Callback (object sender, Foundation.NSNotificationEventArgs args)
{
// Access strongly typed args
Console.WriteLine ("Notification: {0}", args.Notification);
}
void Setup ()
{
notification = UITextView.Notifications.ObserveTextDidBeginEditing (Callback);
}
void Teardown ()
{
notification.Dispose ();
}
適用於
ObserveTextDidBeginEditing(NSObject, EventHandler<NSNotificationEventArgs>)
常數的 TextDidBeginEditingNotification 強型別通知。
public static Foundation.NSObject ObserveTextDidBeginEditing (Foundation.NSObject objectToObserve, EventHandler<Foundation.NSNotificationEventArgs> handler);
static member ObserveTextDidBeginEditing : Foundation.NSObject * EventHandler<Foundation.NSNotificationEventArgs> -> Foundation.NSObject
參數
- objectToObserve
- NSObject
要觀察的物件。
- handler
- EventHandler<NSNotificationEventArgs>
張貼通知時叫用的方法。
傳回
權杖物件,可用來停止接收通知,方法是處置通知或傳遞至 RemoveObservers(IEnumerable<NSObject>)
備註
這個方法可用來訂閱 TextDidBeginEditingNotification 通知。
// Listen to all notifications posted for any object
var token = UITextView.Notifications.ObserveTextDidBeginEditing ((notification) => {
Console.WriteLine ("Observed TextDidBeginEditingNotification!");
};
// Listen to all notifications posted for a single object
var token = UITextView.Notifications.ObserveTextDidBeginEditing (objectToObserve, (notification) => {
Console.WriteLine ($"Observed TextDidBeginEditingNotification for {nameof (objectToObserve)}!");
};
// Stop listening for notifications
token.Dispose ();