ToolStripControlHost.OnSubscribeControlEvents(Control) 方法

定義

命名空間:

System.Windows.Forms

組件:

System.Windows.Forms.dll

從裝載控制項訂閱事件。

protected:
 virtual void OnSubscribeControlEvents(System::Windows::Forms::Control ^ control);

protected virtual void OnSubscribeControlEvents (System.Windows.Forms.Control? control);

abstract member OnSubscribeControlEvents : System.Windows.Forms.Control -> unit
override this.OnSubscribeControlEvents : System.Windows.Forms.Control -> unit

Protected Overridable Sub OnSubscribeControlEvents (control As Control)

參數

control

Control

要訂閱事件的來源控制項。

範例

下列程式碼範例示範如何為主控控制項所公開的事件設定事件處理。 此程式碼範例是針對 類別提供的較大範例的 ToolStripControlHost 一部分。

void OnSubscribeControlEvents( System::Windows::Forms::Control^ c )
{
   // Call the base so the base events are connected.
   __super::OnSubscribeControlEvents( c );
   
   // Cast the control to a MonthCalendar control.
   MonthCalendar^ monthCalendarControl = (MonthCalendar^)c;
   
   // Add the event.
   monthCalendarControl->DateChanged += gcnew DateRangeEventHandler( this, &ToolStripMonthCalendar::HandleDateChanged );
}

protected override void OnSubscribeControlEvents(Control c)
{
    // Call the base so the base events are connected.
    base.OnSubscribeControlEvents(c);

    // Cast the control to a MonthCalendar control.
    MonthCalendar monthCalendarControl = (MonthCalendar) c;

    // Add the event.
    monthCalendarControl.DateChanged +=
        new DateRangeEventHandler(OnDateChanged);
}

Protected Overrides Sub OnSubscribeControlEvents(ByVal c As Control) 

    ' Call the base so the base events are connected.
    MyBase.OnSubscribeControlEvents(c)
    
    ' Cast the control to a MonthCalendar control.
    Dim monthCalendarControl As MonthCalendar = _
        CType(c, MonthCalendar)

    ' Add the event.
    AddHandler monthCalendarControl.DateChanged, _
        AddressOf HandleDateChanged

End Sub

備註

OnSubscribeControlEvents覆寫 方法以新增或防止同步控制事件。

如果您在這裡覆寫並連結事件，請使用 OnUnsubscribeControlEvents 方法將其取消攔截。

引發事件會透過委派叫用此事件處理常式。 如需詳細資訊，請參閱 處理和引發事件。

OnSubscribeControlEvents 方法也允許衍生類別處理事件，而不用附加委派。 這是在衍生類別中處理事件的慣用技巧。

給繼承者的注意事項

當在衍生類別中覆寫 OnSubscribeControlEvents(Control) 時，請確定呼叫基底類別的 OnSubscribeControlEvents(Control) 方法，使已註冊的委派能接收到事件。