ComponentChangedEventHandler Delegate
Assembly: System (in system.dll)
'Declaration <ComVisibleAttribute(True)> _ Public Delegate Sub ComponentChangedEventHandler ( _ sender As Object, _ e As ComponentChangedEventArgs _ ) 'Usage Dim instance As New ComponentChangedEventHandler(AddressOf HandlerMethod)
/** @delegate */ /** @attribute ComVisibleAttribute(true) */ public delegate void ComponentChangedEventHandler ( Object sender, ComponentChangedEventArgs e )
Not applicable.
Parameters
- sender
The source of the event.
- e
A ComponentChangedEventArgs that contains the event data.
When you create a ComponentChangedEventHandler 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. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see Events and Delegates.
A ComponentChanged event will not occur during the loading or unloading of a form because changes are expected during these operations.
This example demonstrates registering a ComponentChangedEventHandler and handling the ComponentChanged event.
Public Sub LinkComponentChangedEvent(ByVal changeService As IComponentChangeService) ' Registers an event handler for the ComponentChanged event. AddHandler changeService.ComponentChanged, AddressOf Me.OnComponentChanged End Sub Private Sub OnComponentChanged(ByVal sender As Object, ByVal e As ComponentChangedEventArgs) ' Displays changed component information on the console. Console.WriteLine(("Type of the component that has changed: " + e.Component.GetType().FullName)) Console.WriteLine(("Name of the member of the component that has changed: " + e.Member.Name)) Console.WriteLine(("Old value of the member: " + e.OldValue.ToString())) Console.WriteLine(("New value of the member: " + e.NewValue.ToString())) End Sub
public void LinkComponentChangedEvent(IComponentChangeService changeService)
{
// Registers an event handler for the ComponentChanged event.
changeService.add_ComponentChanged(new
ComponentChangedEventHandler(this.OnComponentChanged));
} //LinkComponentChangedEvent
private void OnComponentChanged(Object sender, ComponentChangedEventArgs e)
{
// Displays changed component information on the console.
Console.WriteLine("Type of the component that has changed: "
+ e.get_Component().GetType().get_FullName());
Console.WriteLine("Name of the member of the component "
+ "that has changed: " + e.get_Member().get_Name());
Console.WriteLine("Old value of the member: "
+ e.get_OldValue().ToString());
Console.WriteLine("New value of the member: "
+ e.get_NewValue().ToString());
} //OnComponentChanged
Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, 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.