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ComponentEventHandler Delegar

  • Referência

Definição

Namespace:
System.ComponentModel.Design
Assembly:
System.ComponentModel.TypeConverter.dll
Assembly:
System.dll
Assembly:
netstandard.dll

Representa o método que manipulará os eventos ComponentAdding, ComponentAdded, ComponentRemoving e ComponentRemoved gerados para eventos de nível de componente.

public delegate void ComponentEventHandler(System::Object ^ sender, ComponentEventArgs ^ e);
public delegate void ComponentEventHandler(object sender, ComponentEventArgs e);
public delegate void ComponentEventHandler(object? sender, ComponentEventArgs e);
[System.Runtime.InteropServices.ComVisible(true)]
public delegate void ComponentEventHandler(object sender, ComponentEventArgs e);
type ComponentEventHandler = delegate of obj * ComponentEventArgs -> unit
[<System.Runtime.InteropServices.ComVisible(true)>]
type ComponentEventHandler = delegate of obj * ComponentEventArgs -> unit
Public Delegate Sub ComponentEventHandler(sender As Object, e As ComponentEventArgs)

Parâmetros

sender
Object

A fonte do evento.

e
ComponentEventArgs

Um ComponentEventArgs que contém os dados do evento.

Atributos
ComVisibleAttribute

Exemplos

O exemplo a seguir demonstra o registro de um ComponentEventHandler e o tratamento dos ComponentAddedeventos , ComponentAddingComponentRemoved e ComponentRemoving .

public:
   void LinkComponentEvent( IComponentChangeService^ changeService )
   {
      // Registers an event handler for the ComponentAdded,
      // ComponentAdding, ComponentRemoved, and ComponentRemoving events.
      changeService->ComponentAdded += gcnew ComponentEventHandler(
         this, &ComponentEventHandlerExample::OnComponentEvent );
      changeService->ComponentAdding += gcnew ComponentEventHandler(
         this, &ComponentEventHandlerExample::OnComponentEvent );
      changeService->ComponentRemoved += gcnew ComponentEventHandler(
         this, &ComponentEventHandlerExample::OnComponentEvent );
      changeService->ComponentRemoving += gcnew ComponentEventHandler(
         this, &ComponentEventHandlerExample::OnComponentEvent );
   }

private:
   void OnComponentEvent( Object^ sender, ComponentEventArgs^ e )
   {
      // Displays changed component information on the console.
      if ( e->Component->Site != nullptr )
      {
         Console::WriteLine( "Name of the component related to the event: " +
            e->Component->Site->Name );
      }
      Console::WriteLine( "Type of the component related to the event: " +
         e->Component->GetType()->FullName );
   }

public void LinkComponentEvent(IComponentChangeService changeService)
{
    // Registers an event handler for the ComponentAdded,
    // ComponentAdding, ComponentRemoved, and ComponentRemoving events.
    changeService.ComponentAdded += new ComponentEventHandler(this.OnComponentEvent);            
    changeService.ComponentAdding += new ComponentEventHandler(this.OnComponentEvent);            
    changeService.ComponentRemoved += new ComponentEventHandler(this.OnComponentEvent);            
    changeService.ComponentRemoving += new ComponentEventHandler(this.OnComponentEvent);                        
}

private void OnComponentEvent(object sender, ComponentEventArgs e)
{
    // Displays changed component information on the console.            
    if( e.Component.Site != null )
        Console.WriteLine("Name of the component related to the event: "+e.Component.Site.Name);      
    Console.WriteLine("Type of the component related to the event: "+e.Component.GetType().FullName);
}

Public Sub LinkComponentEvent(ByVal changeService As IComponentChangeService)
    ' Registers an event handler for the ComponentAdded,
    ' ComponentAdding, ComponentRemoved, and ComponentRemoving events.
    AddHandler changeService.ComponentAdded, AddressOf Me.OnComponentEvent
    AddHandler changeService.ComponentAdding, AddressOf Me.OnComponentEvent
    AddHandler changeService.ComponentRemoved, AddressOf Me.OnComponentEvent
    AddHandler changeService.ComponentRemoving, AddressOf Me.OnComponentEvent
End Sub

Private Sub OnComponentEvent(ByVal sender As Object, ByVal e As ComponentEventArgs)
    ' Displays changed component information on the console.            
    If (e.Component.Site IsNot Nothing) Then
        Console.WriteLine(("Name of the component related to the event: " + e.Component.Site.Name))
    End If
End Sub

Comentários

Ao criar um ComponentEventHandler delegado, você identifica o método que manipulará o evento. Para associar o evento ao manipulador de eventos, adicione uma instância do delegado ao evento. O manipulador de eventos é chamado sempre que o evento ocorre, a menos que você remova o representante. Para obter mais informações sobre delegados do manipulador de eventos, consulte Manipulando e gerando eventos.

Métodos de Extensão

GetMethodInfo(Delegate)

Obtém um objeto que representa o método representado pelo delegado especificado.

Aplica-se a

Confira também