Form.CancelButton Proprietà

Definizione

Ottiene o imposta il controllo pulsante che verrà selezionato quando l’utente preme il tasto ESC.Gets or sets the button control that is clicked when the user presses the ESC key.

public:
 property System::Windows::Forms::IButtonControl ^ CancelButton { System::Windows::Forms::IButtonControl ^ get(); void set(System::Windows::Forms::IButtonControl ^ value); };
public System.Windows.Forms.IButtonControl CancelButton { get; set; }
member this.CancelButton : System.Windows.Forms.IButtonControl with get, set
Public Property CancelButton As IButtonControl

Valore della proprietà

Oggetto IButtonControl che rappresenta il pulsante di annullamento del form.An IButtonControl that represents the cancel button for the form.

Esempi

Nell'esempio seguente viene creata una nuova istanza di un Form e viene chiamato il metodo ShowDialog per visualizzare il form come finestra di dialogo.The following example creates a new instance of a Form and calls the ShowDialog method to display the form as a dialog box. Nell'esempio vengono impostate le proprietà FormBorderStyle, AcceptButton, CancelButton, MinimizeBox, MaximizeBox e StartPosition per modificare l'aspetto e la funzionalità del form in una finestra di dialogo.The example sets the FormBorderStyle, AcceptButton, CancelButton, MinimizeBox, MaximizeBox, and StartPosition properties to change the appearance and functionality of the form to a dialog box. Nell'esempio viene inoltre usato il metodo Add della raccolta Controls del modulo per aggiungere due controlli Button.The example also uses the Add method of the form's Controls collection to add two Button controls. Nell'esempio viene utilizzata la proprietà HelpButton per visualizzare un pulsante? nella barra del titolo della finestra di dialogo.The example uses the HelpButton property to display a help button in the caption bar of the dialog box.

public:
   void CreateMyForm()
   {
      // Create a new instance of the form.
      Form^ form1 = gcnew Form;
      // Create two buttons to use as the accept and cancel buttons.
      Button^ button1 = gcnew Button;
      Button^ button2 = gcnew Button;
      
      // Set the text of button1 to "OK".
      button1->Text = "OK";
      // Set the position of the button on the form.
      button1->Location = Point(10,10);
      // Set the text of button2 to "Cancel".
      button2->Text = "Cancel";
      // Set the position of the button based on the location of button1.
      button2->Location =
         Point( button1->Left, button1->Height + button1->Top + 10 );
      // Set the caption bar text of the form.   
      form1->Text = "My Dialog Box";
      // Display a help button on the form.
      form1->HelpButton = true;
      
      // Define the border style of the form to a dialog box.
      form1->FormBorderStyle = ::FormBorderStyle::FixedDialog;
      // Set the MaximizeBox to false to remove the maximize box.
      form1->MaximizeBox = false;      
      // Set the MinimizeBox to false to remove the minimize box.
      form1->MinimizeBox = false;
      // Set the accept button of the form to button1.
      form1->AcceptButton = button1;
      // Set the cancel button of the form to button2.
      form1->CancelButton = button2;
      // Set the start position of the form to the center of the screen.
      form1->StartPosition = FormStartPosition::CenterScreen;
      
      // Add button1 to the form.
      form1->Controls->Add( button1 );
      // Add button2 to the form.
      form1->Controls->Add( button2 );
      // Display the form as a modal dialog box.
      form1->ShowDialog();
   }
public void CreateMyForm()
{
   // Create a new instance of the form.
   Form form1 = new Form();
   // Create two buttons to use as the accept and cancel buttons.
   Button button1 = new Button ();
   Button button2 = new Button ();
  
   // Set the text of button1 to "OK".
   button1.Text = "OK";
   // Set the position of the button on the form.
   button1.Location = new Point (10, 10);
   // Set the text of button2 to "Cancel".
   button2.Text = "Cancel";
   // Set the position of the button based on the location of button1.
   button2.Location
      = new Point (button1.Left, button1.Height + button1.Top + 10);
   // Set the caption bar text of the form.   
   form1.Text = "My Dialog Box";
   // Display a help button on the form.
   form1.HelpButton = true;

   // Define the border style of the form to a dialog box.
   form1.FormBorderStyle = FormBorderStyle.FixedDialog;
   // Set the MaximizeBox to false to remove the maximize box.
   form1.MaximizeBox = false;
   // Set the MinimizeBox to false to remove the minimize box.
   form1.MinimizeBox = false;
   // Set the accept button of the form to button1.
   form1.AcceptButton = button1;
   // Set the cancel button of the form to button2.
   form1.CancelButton = button2;
   // Set the start position of the form to the center of the screen.
   form1.StartPosition = FormStartPosition.CenterScreen;
   
   // Add button1 to the form.
   form1.Controls.Add(button1);
   // Add button2 to the form.
   form1.Controls.Add(button2);
   
   // Display the form as a modal dialog box.
   form1.ShowDialog();
}
Public Sub CreateMyForm()
    ' Create a new instance of the form.
    Dim form1 As New Form()
    ' Create two buttons to use as the accept and cancel buttons.
    Dim button1 As New Button()
    Dim button2 As New Button()
       
    ' Set the text of button1 to "OK".
    button1.Text = "OK"
    ' Set the position of the button on the form.
    button1.Location = New Point(10, 10)
    ' Set the text of button2 to "Cancel".
    button2.Text = "Cancel"
    ' Set the position of the button based on the location of button1.
    button2.Location = _
       New Point(button1.Left, button1.Height + button1.Top + 10)
    ' Set the caption bar text of the form.   
    form1.Text = "My Dialog Box"
    ' Display a help button on the form.
    form1.HelpButton = True
       
    ' Define the border style of the form to a dialog box.
    form1.FormBorderStyle = FormBorderStyle.FixedDialog
    ' Set the MaximizeBox to false to remove the maximize box.
    form1.MaximizeBox = False
    ' Set the MinimizeBox to false to remove the minimize box.
    form1.MinimizeBox = False
    ' Set the accept button of the form to button1.
    form1.AcceptButton = button1
    ' Set the cancel button of the form to button2.
    form1.CancelButton = button2
    ' Set the start position of the form to the center of the screen.
    form1.StartPosition = FormStartPosition.CenterScreen
       
    ' Add button1 to the form.
    form1.Controls.Add(button1)
    ' Add button2 to the form.
    form1.Controls.Add(button2)
       
    ' Display the form as a modal dialog box.
    form1.ShowDialog()
End Sub

Commenti

Il pulsante Annulla per un form è il controllo Button su cui si fa clic ogni volta che l'utente preme il tasto ESC.The cancel button for a form is the button control that is clicked whenever the user presses the ESC key. Il pulsante assegnato a questa proprietà deve essere un IButtonControl che si trova nel form corrente o che si trova all'interno di un contenitore nel form corrente.The button assigned to this property must be an IButtonControl that is on the current form or located within a container on the current form.

Questa proprietà consente di designare un'azione predefinita da eseguire quando l'utente preme il tasto ESC nell'applicazione.This property allows you to designate a default action to occur when the user presses the ESC key in your application. È possibile usare questa proprietà per consentire all'utente di spostarsi rapidamente in un modulo semplice consentendo di premere semplicemente il tasto ESC per chiudere una finestra senza eseguire il commit delle modifiche anziché fare clic manualmente sul pulsante Annulla con il mouse.You can use this property to allow the user to quickly navigate a simple form by allowing them to simply press the ESC key to close a window without committing changes instead of manually clicking the cancel button with their mouse.

CancelButton potrebbe non funzionare se un altro controllo del modulo intercetta il tasto ESC.CancelButton may not work if another control on the form intercepts the ESC key. Se, ad esempio, si dispone di un ComboBox aperto nel form, ESC chiuderà il ComboBox anziché chiudere il modulo.For example, if you have a ComboBox open on your form, ESC will close the ComboBox instead of closing the Form.

L'oggetto IButtonControl assegnato a CancelButton deve essere visibile nel form. in caso contrario, la pressione del tasto ESC non avrà alcun effetto.The IButtonControl object assigned to CancelButton must be visible on the form, or else pressing the ESC key will have no effect.

Si applica a

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