Output cache on a usercontrol

Anyone know how to add a outputcache for a usercontrol (.cs file)? I am creating a header control, it will a dll which will be used in all the application. Since it is a header which is almost static I want to cache them. On the Header code it is not a static html, it will be reading the Title, Urls etc from a XML file and draw them using the Output.Write.

I know if it is a acsx file I can add the
<%@ OutputCache Duration="nnn" VaryByParam="ifany" %>

But for a cs class which is part of a dll I am not sure how to add. If anyone have ways to do this it will be great.
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