Form.Closing Form.Closing Form.Closing Form.Closing Event

Definición

Se produce cuando se cierra el formulario.Occurs when the form is closing.

public:
 event System::ComponentModel::CancelEventHandler ^ Closing;
[System.ComponentModel.Browsable(false)]
public event System.ComponentModel.CancelEventHandler Closing;
member this.Closing : System.ComponentModel.CancelEventHandler 
Public Custom Event Closing As CancelEventHandler 
Atributos

Ejemplos

En el ejemplo siguiente Closing se usa para comprobar si el texto TextBox de un ha cambiado.The following example uses Closing to test if the text in a TextBox has changed. Si es así, se pregunta al usuario si desea guardar los cambios en un archivo.If it has, the user is asked whether to save the changes to a file.

private:
   void Form1_Closing( Object^ /*sender*/, System::ComponentModel::CancelEventArgs^ e )
   {
      // Determine if text has changed in the textbox by comparing to original text.
      if ( textBox1->Text != strMyOriginalText )
      {
         // Display a MsgBox asking the user to save changes or abort.
         if ( MessageBox::Show( "Do you want to save changes to your text?", "My Application", MessageBoxButtons::YesNo ) == ::DialogResult::Yes )
         {
            // Cancel the Closing event from closing the form.
            e->Cancel = true;

            // Call method to save file...
         }
      }
   }
private void Form1_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
   // Determine if text has changed in the textbox by comparing to original text.
   if (textBox1.Text != strMyOriginalText)
   {
      // Display a MsgBox asking the user to save changes or abort.
      if(MessageBox.Show("Do you want to save changes to your text?", "My Application",
         MessageBoxButtons.YesNo) ==  DialogResult.Yes)
      {
         // Cancel the Closing event from closing the form.
         e.Cancel = true;
         // Call method to save file...
      }
   }
}
   Private Sub Form1_Closing(sender As Object, e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
      ' Determine if text has changed in the textbox by comparing to original text.
      If textBox1.Text <> strMyOriginalText Then
         ' Display a MsgBox asking the user to save changes or abort.
         If MessageBox.Show("Do you want to save changes to your text?", "My Application", MessageBoxButtons.YesNo) = DialogResult.Yes Then
            ' Cancel the Closing event from closing the form.
            e.Cancel = True
         End If ' Call method to save file...
      End If
   End Sub 'Form1_Closing
End Class 'Form1

Comentarios

Precaución

El Closing evento está obsoleto a partir del .NET Framework 2,0; utilice en FormClosing su lugar el evento.The Closing event is obsolete starting with the .NET Framework 2.0; use the FormClosing event instead.

El Closing evento tiene lugar cuando se cierra el formulario.The Closing event occurs as the form is being closed. Cuando se cierra un formulario, se liberan todos los recursos creados en el objeto y se desecha el formulario.When a form is closed, all resources created within the object are released and the form is disposed. Si cancela este evento, el formulario permanece abierto.If you cancel this event, the form remains opened. Para cancelar el cierre de un formulario, establezca la Cancel propiedad CancelEventArgs del pasado en el controlador de eventos en true.To cancel the closure of a form, set the Cancel property of the CancelEventArgs passed to your event handler to true.

Cuando un formulario se muestra como un cuadro de diálogo modal, al hacer clic en el botón cerrar (el botón con una X en la esquina superior derecha del formulario), se oculta el formulario y DialogResult la propiedad se establece en DialogResult.Cancel.When a form is displayed as a modal dialog box, clicking the Close button (the button with an X at the upper-right corner of the form) causes the form to be hidden and the DialogResult property to be set to DialogResult.Cancel. Puede invalidar el valor asignado a la DialogResult propiedad cuando el usuario haga clic en el botón cerrar estableciendo la DialogResult propiedad en un controlador de eventos para Closing el evento del formulario.You can override the value assigned to the DialogResult property when the user clicks the Close button by setting the DialogResult property in an event handler for the Closing event of the form.

Nota

Cuando se llama al Form Show método en un que se muestra como una ventana no modal, no se puede llamar al método para hacer que el formulario sea visible, ya que los recursos del formulario ya se han liberado. CloseWhen the Close method is called on a Form displayed as a modeless window, you cannot call the Show method to make the form visible, because the form's resources have already been released. Para ocultar un formulario y, a continuación, hacer que esté Control.Hide visible, use el método.To hide a form and then make it visible, use the Control.Hide method.

Precaución

Los Form.Closed eventos Form.Closing y noApplication.Exit se generan cuando se llama al método para salir de la aplicación.The Form.Closed and Form.Closing events are not raised when the Application.Exit method is called to exit your application. Si tiene código de validación en cualquiera de estos eventos que se debe ejecutar, debe llamar al Form.Close método para cada formulario abierto individualmente antes de llamar al Exit método.If you have validation code in either of these events that must be executed, you should call the Form.Close method for each open form individually before calling the Exit method.

Si el formulario es un formulario MDI primario, los Closing eventos de todos los formularios MDI secundarios se generan antes de que se genere Closing el evento del formulario MDI principal.If the form is an MDI parent form, the Closing events of all MDI child forms are raised before the MDI parent form's Closing event is raised. Además, los Closed eventos de todos los formularios MDI secundarios se generan antes de Closed que se produzca el evento del formulario primario MDI.In addition, the Closed events of all MDI child forms are raised before the Closed event of the MDI parent form is raised. Cancelar el Closing evento de un formulario MDI secundario no impide que se genere Closing el evento del formulario primario MDI.Canceling the Closing event of an MDI child form does not prevent the Closing event of the MDI parent form from being raised. Sin embargo, true CancelEventArgs si se cancela el evento, se Cancel establecerá en la propiedad de que se pasa como un parámetro al formulario primario.However, canceling the event will set to true the Cancel property of the CancelEventArgs that is passed as a parameter to the parent form. Para forzar que todos los formularios MDI primarios y secundarios se Cancel cierren false , establezca la propiedad en en el formulario primario MDI.To force all MDI parent and child forms to close, set the Cancel property to false in the MDI parent form.

Para obtener más información sobre el manejo de eventos, consulte controlar y provocar eventos.For more information about handling events, see Handling and Raising Events.

Se aplica a

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