ActiveDesignerEventHandler 委托

定义

命名空间:

System.ComponentModel.Design

程序集:

System.ComponentModel.TypeConverter.dll

表示用来处理 ActiveDesignerChanged 事件的方法。

public delegate void ActiveDesignerEventHandler(System::Object ^ sender, ActiveDesignerEventArgs ^ e);

public delegate void ActiveDesignerEventHandler(object? sender, ActiveDesignerEventArgs e);

type ActiveDesignerEventHandler = delegate of obj * ActiveDesignerEventArgs -> unit

Public Delegate Sub ActiveDesignerEventHandler(sender As Object, e As ActiveDesignerEventArgs)

参数

sender

Object

事件源。

e

ActiveDesignerEventArgs

包含事件数据的 ActiveDesignerEventArgs。

示例

以下示例演示如何注册 ActiveDesignerEventHandler 并处理 ActiveDesignerChanged 事件。

public:
   void LinkActiveDesignerEvent( IDesignerEventService^ eventService )
   {
      // Registers an event handler for the ActiveDesignerChanged event.
      eventService->ActiveDesignerChanged += gcnew ActiveDesignerEventHandler( this, &MiscCompModSamples::ActiveDesignerEventHandlerExample::OnActiveDesignerEvent );
   }

private:
   void OnActiveDesignerEvent( Object^ /*sender*/, ActiveDesignerEventArgs^ e )
   {
      // Displays changed designer information on the console.
      if ( e->NewDesigner->RootComponent->Site != nullptr )
      {
         Console::WriteLine( "Name of the component of the new active designer: {0}", e->NewDesigner->RootComponent->Site->Name );
      }
      Console::WriteLine( "Type of the component of the new active designer: {0}", e->NewDesigner->RootComponentClassName );
      if ( e->OldDesigner->RootComponent->Site != nullptr )
      {
         Console::WriteLine( "Name of the component of the previously active designer: {0}", e->OldDesigner->RootComponent->Site->Name );
      }
      Console::WriteLine( "Type of the component of the previously active designer: {0}", e->OldDesigner->RootComponentClassName );
   }

public void LinkActiveDesignerEvent(IDesignerEventService eventService)
{
    // Registers an event handler for the ActiveDesignerChanged event.
    eventService.ActiveDesignerChanged += new ActiveDesignerEventHandler(this.OnActiveDesignerEvent);
}

private void OnActiveDesignerEvent(object sender, ActiveDesignerEventArgs e)
{
    // Displays changed designer information on the console.
    if( e.NewDesigner.RootComponent.Site != null )
        Console.WriteLine("Name of the component of the new active designer: "+e.NewDesigner.RootComponent.Site.Name);
    Console.WriteLine("Type of the component of the new active designer: "+e.NewDesigner.RootComponentClassName);
    if( e.OldDesigner.RootComponent.Site != null )
        Console.WriteLine("Name of the component of the previously active designer: "+e.OldDesigner.RootComponent.Site.Name);
    Console.WriteLine("Type of the component of the previously active designer: "+e.OldDesigner.RootComponentClassName);
}

Public Sub LinkActiveDesignerEvent(ByVal eventService As IDesignerEventService)
    ' Registers an event handler for the ActiveDesignerChanged event.
    AddHandler eventService.ActiveDesignerChanged, AddressOf Me.OnActiveDesignerEvent
End Sub

Private Sub OnActiveDesignerEvent(ByVal sender As Object, ByVal e As ActiveDesignerEventArgs)
    ' Displays changed designer information on the console.            
    If (e.NewDesigner.RootComponent.Site IsNot Nothing) Then
        Console.WriteLine(("Name of the component of the new active designer: " + e.NewDesigner.RootComponent.Site.Name))
    End If
    Console.WriteLine(("Type of the component of the new active designer: " + e.NewDesigner.RootComponentClassName))
    If (e.OldDesigner.RootComponent.Site IsNot Nothing) Then
        Console.WriteLine(("Name of the component of the previously active designer: " + e.OldDesigner.RootComponent.Site.Name))
    End If
    Console.WriteLine(("Type of the component of the previously active designer: " + e.OldDesigner.RootComponentClassName))
End Sub

注解

修改 ActiveDesignerChanged 当前活动文档时，将引发 该事件。

创建 ActiveDesignerEventHandler 委托时，需要标识将要处理该事件的方法。 若要将事件与事件处理程序关联，请将该委托的一个实例添加到事件中。 除非移除了该委托，否则每当发生该事件时就会调用事件处理程序。 有关事件处理程序委托的详细信息，请参阅 处理和引发事件。

扩展方法

GetMethodInfo(Delegate)

获取指示指定委托表示的方法的对象。

另请参阅

• ActiveDesignerEventArgs
• ActiveDesignerChanged