class-handlers.md

Class Handlers

In WPF, class handlers for events can be added by calling EventManager.RegisterClassHandler. An example of registering a class handler in WPF might be:

static MyControl()
{
    EventManager.RegisterClassHandler(typeof(MyControl), MyEvent, HandleMyEvent));
}

private static void HandleMyEvent(object sender, RoutedEventArgs e)
{
}

static MyControl()
{
    MyEvent.AddClassHandler<MyControl>((x, e) => x.HandleMyEvent(e));
}

private void HandleMyEvent(RoutedEventArgs e)
{
}

Notice that in WPF you have to add the class handler as a static method, whereas in Avalonia the class handler is not static: the notification is automatically directed to the correct instance. The sender parameter typical of event handlers is not necessary in this case and everything remains strongly typed.