Form.CancelButton 屬性

定義

命名空間:

System.Windows.Forms

組件:

System.Windows.Forms.dll

來源:

Form.cs

使用者按下 ESC 鍵時，會取得或設定按鈕控制。

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

屬性值

IButtonControl

那 IButtonControl 代表表單的取消按鈕。

範例

以下範例建立一個新的實例 Form ，並呼叫該 ShowDialog 方法以對話框顯示表單。 範例中設定FormBorderStyle了 、 AcceptButton、 MaximizeBoxCancelButtonMinimizeBoxStartPosition 、 和 屬性，以改變表單的外觀與功能，呈現對話框。 範例也利用 Add 表單 Controls 收集方法加入兩個 Button 控制項。 範例中利用該 HelpButton 屬性在對話框的說明欄中顯示一個幫助按鈕。

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

備註

表單的取消按鈕是使用者按下 ESC 鍵時所點擊的按鈕控制鍵。 分配給此屬性的按鈕必須是 IButtonControl 目前表單上的 a 或位於當前表單容器中的按鈕。

這個特性讓你能指定當使用者按下應用程式中的 ESC 鍵時，預設執行的動作。 你可以利用這個特性，讓使用者只需按下 ESC 鍵就能關閉視窗，而不必手動用滑鼠點擊取消按鈕，從而快速瀏覽簡單的表單。

CancelButton 如果表單上的另一個控制攔截了 ESC 鍵，可能就無法運作。 例如，如果你的表單有 ComboBox 空缺，ESC 會關閉表 ComboBox 單而不是關閉表單。

IButtonControl指派到CancelButton的物件必須在表單上可見，否則按下 ESC 鍵也不會有效果。

另請參閱

• AcceptButton
• IButtonControl