Is it possible to have an editbox where the vertical scrollbar only appears if necessary?

I believe I can compute how many lines will fit in an editbox, but know of no way in which I can
tell how many lines will be displayed because of the automatic line wrap.

Two things I need to mention:
(1) This editbox is disabled, so I don't have to be concerned with what happens with user input.
(2) I can't use any other control instead, it must be an editbox.

Thanks