VB.NET RemoveHandler&匿名方法 [英] VB.NET RemoveHandler & Anonymous Methods

问题描述

如何将 RemoveHandler 与匿名方法一起使用？

How do I use RemoveHandler with anonymous methods?

这是我为<$添加处理程序的方式 MyClass 类的c $ c> MyEvent 事件：

This is how I add a handler for MyEvent event of the class MyClass:

AddHandler MyClass.MyEvent, Sub()
                                '...
                            End Sub

然后如何使用 RemoveHandler 删除 MyEvent 事件的处理程序？

How do I then use RemoveHandler to remove the handler for the MyEvent event?

推荐答案

通常，如果您需要退订该事件，建议不要使用像这样的lambda，而应使用标准方法

In general, if you need to unsubscribe from the event, I would recommend not using a lambda like this, and instead use a standard method.

话虽如此，您仍然可以使用匿名方法，但是需要为取消订阅存储对它的引用。如果必须取消订阅匿名方法，则至少应将委托存储在变量中，以便以后将其删除：

That being said, you can still use the anonymous method, but you need to store a reference to it for the unsubscription. If you must unsubscribe an anonymous method, at a minimum, you should store the delegate in a variable to remove it later:

Dim subscription = Sub()
                            ' ...
                   End Sub

AddHandler MyClass.MyEvent, subscription

' Later   
RemoveHandler MyClass.MyEvent, subscription

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