Send querystring params as part of form post

A friend of mine showed me what I believe is an easier way:

<% form_tag params.merge(:action=>"someAction") do %>

Merging params into the hash necessary for making the form_tag did the trick perfectly.

The preferred way would be to use hidden fields. I haven't tried it, but I think you can specify additional query string parameters within the *_path or *_url helpers. Something like:

<% form_for(@post,
           :url => post_path(@post, :foo => 'foo', :bar => 'bar')) do |f| %>
  ...
<% end %>