ToolStripControlHost.OnSubscribeControlEvents(Control) 方法
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
向托管控件订阅事件。
protected:
virtual void OnSubscribeControlEvents(System::Windows::Forms::Control ^ control);
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)
参数
- control
- Control
向其订阅事件的控件。
示例
下面的代码示例演示如何为托管控件公开的事件设置事件处理。 此代码示例是为 ToolStripControlHost 类提供的一个更大示例的一部分。
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
注解
OnSubscribeControlEvents重写 方法以添加或阻止控件事件的同步。
如果在此处重写并挂接事件,请使用 OnUnsubscribeControlEvents 方法取消挂钩事件。
引发事件时,将通过委托调用事件处理程序。 有关详细信息,请参阅 处理和引发事件。
OnSubscribeControlEvents 方法还允许派生类对事件进行处理而不必附加委托。 这是在派生类中处理事件的首选技术。
继承者说明
在派生类中重写 OnSubscribeControlEvents(Control) 时,一定要调用基类的 OnSubscribeControlEvents(Control) 方法,以便已注册的委托对事件进行接收。