ToolStripControlHost.OnUnsubscribeControlEvents(Control) 方法

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

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

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

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

Protected Overridable Sub OnUnsubscribeControlEvents (control As Control)

參數

範例

以下程式碼範例示範如何取消訂閱由託管控制所暴露的事件。 此程式碼範例是本類別更大範例 ToolStripControlHost 的一部分。

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

protected override void OnUnsubscribeControlEvents(Control c)
{
    // Call the base method so the basic events are unsubscribed.
    base.OnUnsubscribeControlEvents(c);

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

    // Remove the event.
    monthCalendarControl.DateChanged -=
        new DateRangeEventHandler(OnDateChanged);
}

Protected Overrides Sub OnUnsubscribeControlEvents(ByVal c As Control)
    ' Call the base method so the basic events are unsubscribed.
    MyBase.OnUnsubscribeControlEvents(c)

    ' Cast the control to a MonthCalendar control.
    Dim monthCalendarControl As MonthCalendar = _
        CType(c, MonthCalendar)

    ' Remove the event.
    RemoveHandler monthCalendarControl.DateChanged, _
        AddressOf HandleDateChanged

End Sub

備註

覆寫 OnUnsubscribeControlEvents 取消訂閱事件 OnSubscribeControlEvents的方法。

發起事件會透過代理呼叫事件處理者。 欲了解更多資訊，請參閱 處理與提升事件。

此 OnUnsubscribeControlEvents 方法也允許衍生類別在不附加代理的情況下處理事件。 這是在衍生類別中處理事件的首選技術。

給繼承者的注意事項

在導出類別中覆寫 OnUnsubscribeControlEvents(Control) 時，務必呼叫基底類別的方法 OnUnsubscribeControlEvents(Control) ，讓註冊代理接收事件。