MenuCommand.OnCommandChanged(EventArgs) 方法
定义
引发 CommandChanged 事件。Raises the CommandChanged event.
protected:
virtual void OnCommandChanged(EventArgs ^ e);
protected virtual void OnCommandChanged (EventArgs e);
abstract member OnCommandChanged : EventArgs -> unit
override this.OnCommandChanged : EventArgs -> unit
Protected Overridable Sub OnCommandChanged (e As EventArgs)
参数
注解
引发事件时,将通过委托调用事件处理程序。Raising an event invokes the event handler through a delegate. 有关详细信息,请参阅 处理和引发事件。For more information, see Handling and Raising Events.
OnCommandChanged 方法还允许派生类对事件进行处理而不必附加委托。The OnCommandChanged method also allows derived classes to handle the event without attaching a delegate. 这是在派生类中处理事件的首选技术。This is the preferred technique for handling the event in a derived class.
继承者说明
当 OnCommandChanged(EventArgs) 在派生类中重写时,请确保调用基类的 OnCommandChanged(EventArgs) 方法,以便注册的委托接收事件。When overriding OnCommandChanged(EventArgs) in a derived class, be sure to call the base class' OnCommandChanged(EventArgs) method so that registered delegates receive the event.