Control.OnLeave(EventArgs) Control.OnLeave(EventArgs) Control.OnLeave(EventArgs) Control.OnLeave(EventArgs) Method

Definición

Genera el evento Leave.Raises the Leave event.

protected:
 virtual void OnLeave(EventArgs ^ e);
protected virtual void OnLeave (EventArgs e);
abstract member OnLeave : EventArgs -> unit
override this.OnLeave : EventArgs -> unit
Protected Overridable Sub OnLeave (e As EventArgs)

Parámetros

e
EventArgs EventArgs EventArgs EventArgs

Objeto EventArgs que contiene los datos del evento.An EventArgs that contains the event data.

Ejemplos

En el ejemplo de código siguiente Leave se utiliza el evento para restablecer el estado anterior de un control.The following code example uses the Leave event to reset a control to its former state.

private:
   void textBox1_Enter( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // If the TextBox contains text, change its foreground and background colors.
      if ( textBox1->Text != String::Empty )
      {
         textBox1->ForeColor = Color::Red;
         textBox1->BackColor = Color::Black;

         // Move the selection pointer to the end of the text of the control.
         textBox1->Select(textBox1->Text->Length,0);
      }
   }

   void textBox1_Leave( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Reset the colors and selection of the TextBox after focus is lost.
      textBox1->ForeColor = Color::Black;
      textBox1->BackColor = Color::White;
      textBox1->Select(0,0);
   }
private void textBox1_Enter(object sender, System.EventArgs e)
{
    // If the TextBox contains text, change its foreground and background colors.
    if (!string.IsNullOrEmpty(textBox1.Text))
    {
        textBox1.ForeColor = Color.Red;
        textBox1.BackColor = Color.Black;
        // Move the selection pointer to the end of the text of the control.
        textBox1.Select(textBox1.Text.Length, 0);
    }
}

private void textBox1_Leave(object sender, System.EventArgs e)
{
    // Reset the colors and selection of the TextBox after focus is lost.
    textBox1.ForeColor = Color.Black;
    textBox1.BackColor = Color.White;
    textBox1.Select(0,0);
}
    Private Sub textBox1_Enter(sender As Object, e As System.EventArgs) Handles textBox1.Enter
        ' If the TextBox contains text, change its foreground and background colors.
        If textBox1.Text <> [String].Empty Then
            textBox1.ForeColor = Color.Red
            textBox1.BackColor = Color.Black
            ' Move the selection pointer to the end of the text of the control.
            textBox1.Select(textBox1.Text.Length, 0)
        End If
    End Sub 'textBox1_Enter
   
   
    Private Sub textBox1_Leave(sender As Object, e As System.EventArgs) Handles textBox1.Leave
        ' Reset the colors and selection of the TextBox after focus is lost.
        textBox1.ForeColor = Color.Black
        textBox1.BackColor = Color.White
        textBox1.Select(0, 0)
    End Sub 'textBox1_Leave
End Class 'Form1 

Comentarios

Cuando se genera un evento, se invoca el controlador de eventos a través de un delegado.Raising an event invokes the event handler through a delegate. Para obtener más información, consulte controlar y provocar eventos.For more information, see Handling and Raising Events.

El método OnLeave también permite que las clases derivadas controlen el evento sin adjuntar ningún delegado.The OnLeave method also allows derived classes to handle the event without attaching a delegate. Ésta es la técnica preferida para controlar el evento en una clase derivada.This is the preferred technique for handling the event in a derived class.

Notas a los desarrolladores de herederos

Al reemplazar OnLeave(EventArgs) en una clase derivada, asegúrese de llamar al método OnLeave(EventArgs) de la clase base para que los delegados registrados reciban el evento.When overriding OnLeave(EventArgs) in a derived class, be sure to call the base class's OnLeave(EventArgs) method so that registered delegates receive the event.

Se aplica a

Consulte también: