Directx Classes

I was trying to create a group of classes to facilitate the use of DirectX ,but then I came into a thought: "How I''m going to create a long living class,if new versions of DirectX comes out every six months? ". The first solution I tought was using a template and good abstraction,so that for the new versions I would only change the functions bodies ,and not the class itself. I would like to know from the more experienced ,how you guys handle these new versions of directx,if you rewrite everything, or have a trick that allow a minimum change in the code for each new version.