Pass method as parameter to another method

Hey guys,

I try to build a Class-around for an GUI.Button() …
In this case I want to make some calls possible like:

Button btn = new Button();
btn.addClickEvent(<Methodname || anonymus method>);

But how has the method Looks like? What Parameter have to be in it?

Thank you very much for all helpful and well meaned answers.

PS: Maybe it’s good to say, that I use C#