How to pass data from jQuery to controller?

I have two fields - end and start date(daterange) and I should pass them into controller and reload this page.

Here is my code from view:

    <%= form_tag(:controller => "financial_reports", :action => 'index', :method => 'post') do%>//maybe this line should be edited
   <%= datepicker_input "report","start_date", :dateFormat => "dd/mm/yy" %>
  <%= datepicker_input "report", "end_date", :dateFormat => "dd/mm/yy"%>
  <%end%>

and generated HTML() :

  <form accept-charset="UTF-8" action="/financial_reports?method=post" method="post"...>
  <input id="report_start_date" name="report[start_date]" size="30" type="text" class="hasDatepicker"><script type="text/javascript">
<input id="report_end_date" name="report[end_date]" size="30" type="text" class="hasDatepicker"
    <input class="btn wide" id="btn-report" name="commit" type="submit" value="Run Report">
  </form>

Can I get datepicker value like this :

      $('#datepicker').datepicker({
    onSelect: function(dateText, inst) {
  $("input[name='report[start_date]']").val(dateText);
    }
});

and I need to pass them into controller and reload this page, because in this page controller.

HERE I NEED TO PASS JQUERY VALUE

    @financial_reports = current_user.financial_reports.where(:created_at => start_date.to_date..end_date.to_date)

or I should add another action or method ? What you can suggest ?

In my opinion, using AJAX and not reloading the page is a best bet here. You're simply trying to update some data, and there's no reason to perform a full page-refresh to do that. I'm not a RoR aficionado, but it would seem that we can send the data to the controller by doing ->

$.ajax({ 
  type: 'POST', 
  url: 'path/to/controller', 
  data: {'start_date' : $("input[name='report[start_date]']").val(), 
        'end_date' : $("input[name='report[end_date]']").val() }, 
  success: function(data){
    //data is whatever you RETURN from your controller. 
    //an array, string, object...something 
  } 
});`

In your RoR controller, you'll get the params by doing...

var the_start = params[:start_date],
    the_end = params[:end_date]

Now you've got the data in your controller, you can apply the method to it. Then when you're ready to send the data back, return, print, whatever you do to send data to the page.

Also, RoR by default (when accessing a controller) expects to output a template to the view, since we just want to update data, you'll need to stop that default action using something like ->