Textfield helper - formatting the displayed text

Is there a way to have a textfield helper format the displayed field?
like to invoke the number_to_currency method on the number that get’s
displayed, but I can’t figure out how to do it. I tried:

<%= text_field ‘product’, number_to_currency(‘price’) %> and that didn’t
seem to work…

Will I just have to use regular html if I want to achieve this?