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移除wpf窗口中的事件处理程序
原标题:Removing event handlers in wpf window

在我们的wpf应用程序中,我们正在构造窗口时添加事件,像这样:

AddHandler(Keyboard.KeyUpEvent, (KeyEventHandler)HandleKeyDownEvent);

        this.Closing += new System.ComponentModel.CancelEventHandler(WindowF_Closing);
        this.Loaded += new RoutedEventHandler(WindowF_Loaded);

在关闭事件中删除这些事件以使窗口被处理,这是个好主意吗?

RemoveHandler(Keyboard.KeyUpEvent, (KeyEventHandler)HandleKeyDownEvent);

        this.Closing -= new System.ComponentModel.CancelEventHandler(WindowF_Closing);
        this.Loaded -= new RoutedEventHandler(WindowF_Loaded);
问题回答

只有在事件的发布者的寿命比订阅者更长时,您才需要显式删除事件处理程序。

在您的情况下,ClosingLoaded事件的发布者是窗口本身,因此无需从事件中取消订阅。然而,键盘将在很长一段时间内存在,因此从KeyUpEvent取消订阅是一个好主意。





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