changing output format based on submission-passed paramater

gistfile1.rb

#incidents_controller.rb:

if params[:commit] == I18n.t(:text_search_results)
  self.request.format = "text"
end

format.text do
  self.response.headers["Content-Type"] ||= 'text/plain'
  self.response.headers["Content-Disposition"] =
    "attachment; filename=search.txt"
  self.response.headers['Last-Modified'] = Time.now.ctime.to_s
  self.response_body = Enumerator.new do |yielder|
    @incidents.each do |incident|
      yielder.yield incident.to_text + "\n"
    end
  end
end

# incidents viewer index.html.erb:

<%= submit_tag t(:text_search_results)  %>