does DOM order determine the order of form parameters posted?

Question

If I have a form like this:

Answer 1

This is the standard. I find that the W3C specification is very useful and readable.

application/x-www-form-urlencoded...

The control names/values are listed in the order they appear in the document.

multipart/form-data...

The parts are sent to the processing agent in the same order the corresponding controls appear in the document stream.

I have yet to encounter a browser that doesn't follow this convention, so I'd say you're pretty safe to use it.

That being said, my semantic bone is a bit uncomfortable with relying on this convention. If ordering is crucial, I would instead use:

<form>
  <input name="param[0]" />
  <input name="param[1]" />
  <input name="param[2]" />
</form>