What happens if the action field in a <form> has parameters?

Question

Is there a well-supported, common behavior that I can expect if I do something like this in HTML:

Answer 1

Well, all the questions have been answered except the last, to which the answer is yes. For POST, it's allowed, but you may well find cases where it doesn't work. I've seen web servers that only allow postdata or querystring, so it's not dependable.