RemoveHandler Method

DependencyObject.RemoveHandler Method

Removes an EventHandler from an associated DependencyProperty.

Namespace: System.Workflow.ComponentModel
Assembly: System.Workflow.ComponentModel (in system.workflow.componentmodel.dll)

public void RemoveHandler (
	DependencyProperty dependencyEvent,
	Object value
public void RemoveHandler (
	DependencyProperty dependencyEvent, 
	Object value
public function RemoveHandler (
	dependencyEvent : DependencyProperty, 
	value : Object
Not applicable.



The DependencyProperty.


The Object representing the value of this property. In this case, a Delegate type.

Exception typeCondition


Either of the arguments is a null reference (Nothing in Visual Basic).


The dependencyEvent is a metaproperty.


The dependencyEvent is not an event.


The value is a ActivityBind and this instance is not in DesignMode.

Provided as a convenient direct method for removing an event delegate.

When you create a delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. Unless you remove the delegate, the event handler is called whenever the event occurs. For more information about event-handler delegates, see Events and Delegates.

Handlers are added and removed using the following code. See Send E-mail Activity Sample for more information.

#region Public Events

[Description("The SendingEmail event is raised before an email is sent through SMTP.")]
public event EventHandler SendingEmail
        base.AddHandler(SendEmailActivity.SendingEmailEvent, value);
        base.RemoveHandler(SendEmailActivity.SendingEmailEvent, value);

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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