CancelEventArgs CancelEventArgs CancelEventArgs CancelEventArgs Class

Definición

public ref class CancelEventArgs : EventArgs

public class CancelEventArgs : EventArgs

type CancelEventArgs = class
    inherit EventArgs

Public Class CancelEventArgs
Inherits EventArgs

Herencia

ObjectObjectObjectObject

EventArgsEventArgsEventArgsEventArgs

CancelEventArgsCancelEventArgsCancelEventArgsCancelEventArgs

Derivado

StartupEventArgsStartupEventArgsStartupEventArgsStartupEventArgs

DoWorkEventArgsDoWorkEventArgsDoWorkEventArgsDoWorkEventArgs

SettingChangingEventArgsSettingChangingEventArgsSettingChangingEventArgsSettingChangingEventArgs

PrintEventArgsPrintEventArgsPrintEventArgsPrintEventArgs

ErrorEventArgsErrorEventArgsErrorEventArgsErrorEventArgs

Más…

Ejemplos

En el ejemplo siguiente se usa CancelEventArgs y un CancelEventHandler para controlar la Closing eventos de un Form.The following example uses CancelEventArgs and a CancelEventHandler to handle the Closing event of a Form. Este código supone que ha creado un Form con un nivel de clase Boolean variable denominada isDataSaved.This code assumes that you have created a Form with a class-level Boolean variable named isDataSaved. También se supone que ha agregado una instrucción para invocar el OtherInitialize método desde el formulario Load método o el constructor (después de llamar a InitializeComponent).It also assumes that you have added a statement to invoke the OtherInitialize method from the form's Load method or the constructor (after the call to InitializeComponent).

private:
   // Call this method from the InitializeComponent() method of your form
   void OtherInitialize()
   {
      this->Closing += gcnew CancelEventHandler( this, &Form1::Form1_Cancel );
      this->myDataIsSaved = true;
   }

   void Form1_Cancel( Object^ /*sender*/, CancelEventArgs^ e )
   {
      if ( !myDataIsSaved )
      {
         e->Cancel = true;
         MessageBox::Show( "You must save first." );
      }
      else
      {
         e->Cancel = false;
         MessageBox::Show( "Goodbye." );
      }
   }

// Call this method from the constructor of your form
    private void OtherInitialize() {
       this.Closing += new CancelEventHandler(this.Form1_Closing);
       // Exchange commented line and note the difference.
       this.isDataSaved = true;
       //this.isDataSaved = false;
    }

    private void Form1_Closing(Object sender, CancelEventArgs e) {
       if (!isDataSaved) {
          e.Cancel = true;
          MessageBox.Show("You must save first.");
       }
       else {
          e.Cancel = false;
          MessageBox.Show("Goodbye.");
       }
    }
 

' Call this method from the Load method of your form.
Private Sub OtherInitialize()
    ' Exchange commented line and note the difference.
    Me.isDataSaved = True
    'Me.isDataSaved = False
End Sub 'OtherInitialize

Private Sub Form1_Closing(sender As Object, e As _
   System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
    If Not isDataSaved Then
        e.Cancel = True
        MessageBox.Show("You must save first.")
    Else
        e.Cancel = False
        MessageBox.Show("Goodbye.")
    End If
End Sub 'Form1_Closing

Comentarios

Componente provoca un evento cancelable cuando está a punto de realizar una acción que puede cancelarse, como el Closing eventos de un Form.A cancelable event is raised by a component when it is about to perform an action that can be canceled, such as the Closing event of a Form.

CancelEventArgs proporciona el Cancel propiedad para indicar si se debe cancelar el evento.CancelEventArgs provides the Cancel property to indicate whether the event should be canceled.

Constructores

Propiedades

Métodos

Se aplica a

Consulte también:

• CancelEventHandler