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RoutedEvent Class

Represents and identifies a routed event and declares its characteristics.

Namespace:  System.Windows
Assembly:  PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
[TypeConverterAttribute("System.Windows.Markup.RoutedEventConverter, PresentationFramework, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, Custom=null")]
public sealed class RoutedEvent
<object property="eventName"/>
- or -
<object property="type.eventName"/>

XAML Values

eventName

An unqualified event name, equivalent to the Name property of the RoutedEvent field, not the actual member name of the RoutedEvent identifier field within a type. Without qualification, eventName must name an event as found in the type that is the TargetType of the current style containing the EventSetter or EventTrigger.

type

The type to use to qualify the event name. If provided without a prefix, type is expected to be a class within the default namespace. For custom events, or events that are on types outside of the default XML namespace (typically the default is the WPF namespace), this type can be prefixed with a mapped XML namespace prefix that contains the type with the desired routed event identifier. For details on namespace mapping, see XAML Namespaces and Namespace Mapping.

This class contains the Name, RoutingStrategy, HandlerType, and OwnerType properties. None of these members can be null.

This class has a XAML usage that is exclusively intended for providing the value of the RoutedEvent property of an EventTrigger (or derived class), or for the Event property of an EventSetter (or derived class). For more information about EventTrigger, EventSetter, and the XAML usages for those classes, see Routed Events Overview.

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 How to: Handle a Routed Event.

System.Object
  System.Windows.RoutedEvent
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 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0
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