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EventManager Class

Provides event-related utility methods that register routed events for class owners and add class handlers.

Namespace: System.Windows
Assembly: PresentationCore (in presentationcore.dll)
XML Namespace:  http://schemas.microsoft.com/winfx/2006/xaml/presentation

public static class EventManager
public final class EventManager
public final class EventManager
You cannot use this managed class in XAML.

This class is most commonly used to register a new routed event, with RegisterRoutedEvent.

The second most common API usage is RegisterClassHandler. You use this method to enable class handling of an event on a class that derives from the owner class of the event. For details, see Marking Routed Events as Handled, and Class Handling.

The following example show how to use this class to register a new routed event.

For your custom event to support event routing, you need to register a RoutedEvent using the RegisterRoutedEvent method. This example demonstrates the basics of creating a custom routed event.

As shown in the following example, you first register a RoutedEvent using the RegisterRoutedEvent method. By convention, the RoutedEvent static field name should end with the suffix Event. In this example, the name of the event is Tap and the routing strategy of the event is Bubble. After the registration call, you can provide add-and-remove common language runtime (CLR) event accessors for the event.

Note that even though the event is raised through the OnTap virtual method in this particular example, how you raise your event or how your event responds to changes depends on your needs.

Note also that this example basically implements an entire subclass of Button; that subclass is built as a separate assembly and then instantiated as a custom class on a separate Extensible Application Markup Language (XAML) page. This is to illustrate the concept that subclassed controls can be inserted into trees composed of other controls, and that in this situation, custom events on these controls have the very same event routing capabilities as any native Windows Presentation Foundation (WPF) element does.

public class MyButtonSimple: Button
{
    // Create a custom routed event by first registering a RoutedEventID
    // This event uses the bubbling routing strategy
    public static readonly RoutedEvent TapEvent = EventManager.RegisterRoutedEvent("Tap", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(MyButtonSimple));

    // Provide CLR accessors for the event
    public event RoutedEventHandler Tap
       {
              add { AddHandler(TapEvent, value); } 
              remove { RemoveHandler(TapEvent, value); }
       }

    // This method raises the Tap event
       void RaiseTapEvent()
       {
              RoutedEventArgs newEventArgs = new RoutedEventArgs(MyButtonSimple.TapEvent);
              RaiseEvent(newEventArgs);
      }
    // For demonstration purposes we raise the event when the MyButtonSimple is clicked
    protected override void OnClick()
    {
        RaiseTapEvent();
    }

}

<Window  
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:custom="clr-namespace:SDKSample;assembly=SDKSampleLibrary"
    x:Class="SDKSample.RoutedEventCustomApp"

    >
    <Window.Resources>
      <Style TargetType="{x:Type custom:MyButtonSimple}">
        <Setter Property="Height" Value="20"/>
        <Setter Property="Width" Value="250"/>
        <Setter Property="HorizontalAlignment" Value="Left"/>
        <Setter Property="Background" Value="#808080"/>
      </Style>
    </Window.Resources>
    <StackPanel Background="LightGray">
	    <custom:MyButtonSimple Name="mybtnsimple" Tap="TapHandler">Click to see Tap custom event work</custom:MyButtonSimple>
    </StackPanel>
</Window>

Tunneling events are created the same way, but with RoutingStrategy set to Tunnel in the registration call. By convention, tunneling events in WPF are prefixed with the word "Preview".

To view the complete sample, including the implementation of the actual "Tap" event handler, see Custom Routed Events Sample. To see an example of how bubbling events work, see Handle a Routed Event.

System.Object
  System.Windows.EventManager

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0

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