Sorting(and updating) multiple lists on one page

If I understand correctly, the problem is that you don't know in your
action whether to expect params[:itemlist1], or params[:itemlistN].
You could try something like:

params.to_a.each do |key, value|
  if key.index('itemlist') == 0
    order = params[key]
    # Process the order
  end
end

Cheers,
Chris