Add string from form input to URL using Codeigniter

I have a div containing a search box:

<div id="searchbox">
    <?php echo form_open('places/search/sort_by/id/sort_order/desc/term/'.$this->input->post('term')); ?>
        <?php echo form_label('Search for', 'term'); ?>
        <?php echo form_input('term', set_value('term'), 'id="term"'); ?>
        <?php echo form_submit('submit', 'Search'); ?>
    <?php echo form_close(); ?>
</div>

In the input the user can type in a search term, which will be given to the controller using $this->input->post('term') which then passes to the model to query the database. Now after typging in the search term and submitting the form, I want the url to end with the search term ie. places/search/sort_by/id/sort_order/desc/term/dinosaur if 'dinosaur' was the search term. How can I do this?

Right now the code above passes the POST to controller, but the url right after submitting the form is just places/search/sort_by/id/sort_order/desc/term/. Then if the user searches for another term say 'cats', after submitting the url becomes places/search/sort_by/id/sort_order/desc/term/dinosaur when the search term is actually 'cats'.

How can I solve this?

In other words, this is the behavior i want

1. URL is places/search/sort_by/id/sort_order/desc/term/ and search box is empty
2. 'Dinosaur' is typed into search box, and press submit
3. URL is now places/search/sort_by/id/sort_order/desc/term/dinosaur and search box contains 'dinosaur'
4. 'cats' is typed into search box, and press submit
5. URL is now places/search/sort_by/id/sort_order/desc/term/cats and search box contains 'cats'

This is what I am getting with the above c开发者_如何学Pythonode

1. URL is places/search/sort_by/id/sort_order/desc/term/ and search box is empty
2. 'Dinosaur' is typed into search box, and press submit

3. URL is now places/search/sort_by/id/sort_order/desc/term/ and search box contains 'dinosaur'

4. 'cats' is typed into search box, and press submit

5. URL is now places/search/sort_by/id/sort_order/desc/term/dinosaur and search box contains 'cats'

Try this...

<div id="searchbox">
    <?php echo form_open('places/search/sort_by/id/sort_order/desc/term/'); ?>
        <?php echo form_label('Search for', 'term'); ?>
        <?php echo form_input('term', set_value('term', $term), 'id="term"'); ?>
        <?php echo form_submit('submit', 'Search'); ?>
    <?php echo form_close(); ?>
</div>

Then in the controller that accepts it...

                      // Note the default NULL value for the last uri segment
                     //                                                   |
                    //                                                    v
function search($sort_by, $id, $sort_order, $desc, $term, $search_term = NULL)
{
     // if $search_term is null redirect on itself concating the "post" data 
    // on the end of the uri
    if ($search_term === NULL) 
    { 
        redirect('the/same/uri/plus/the/term/'.$this->input->post('term'));
    }

    // load up this variable to fill the input
    $data['term'] = $search_term;

    //then do whatever

}