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

El siguiente ejemplo de código usa Closing para probar si el texto en un TextBox ha cambiado.The following code example uses Closing to test if the text in a TextBox has changed. Si es así, es que el usuario le pregunte 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 en .NET Framework versión 2.0; utilice el FormClosing eventos en su lugar.The Closing event is obsolete in the .NET Framework version 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 dentro del objeto y se elimina 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 de la CancelEventArgs pasa al controlador de eventos true.To cancel the closure of a form, set the Cancel property of the CancelEventArgs passed to your event handler to true.

Cuando se muestra un formulario como cuadro de diálogo modal, al hacer clic en el cerrar botón (el botón con una X en la esquina superior derecha del formulario) hace que el formulario se oculta y la DialogResult 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 hace clic en el cerrar botón estableciendo la DialogResult propiedad en un controlador de eventos para el Closing 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 el Close se llama al método en un Form muestra como una ventana no modal y no se puede llamar el Show método para que el formulario esté visible, porque ya se han publicado los recursos del formulario.When 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, hacerlo visible, use el Control.Hide método.To hide a form and then make it visible, use the Control.Hide method.

Precaución

El Form.Closed y Form.Closing no son de eventos se produce cuando el Application.Exit método se llama 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 deben ejecutar, debe llamar a la Form.Close método para cada formulario abierto individualmente antes de llamar a la 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, el Closing se generan eventos de todos los formularios MDI secundarios antes del formulario primario MDI Closing provoca el evento.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, el Closed se generan eventos de todos los formularios MDI secundarios antes de la Closed se provoca 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. Cancelando la Closing eventos de un formulario MDI secundario no impide que el Closing eventos del formulario MDI primario que se generen.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, al cancelar el evento establecerá en true el Cancel propiedad de la CancelEventArgs que se pasa como parámetro al formulario principal.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 cierren, establezca el Cancel propiedad false en el MDI formulario primario.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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