I have one question, let me take an example. when a user visits:
http://www.ruby-forum.com/topic/new?forum_id=3
it will show a form that has forum, name, email, subject, text five
fields for posting. right?
I want to provide more features on this form page, when the user choose
a different forum from the first drop list, the form will show more
different fields, such as a time selecor, or an option or what ever I
want to show to my users.
how can I do use ruby/rails or javascript? thanks in advance.