Populate Dynamic Dropdowns List in Codeigniter

Question

Database inlcude Groups like Arts,Science and IT.By Choosing one Group Second Dynamic Dropdown appear which will show the Subjects Related to Group. This is my View

   <?php include('admin_header.php'); ?>
   <body id="page-wrapper">
 <div class="container-fluid">
    <h1 class="text-center">Enter Courses</h1>
 <hr>
 </div>
 <?php if($feedback = $this->session->flashdata('feedback')):
  $feedback_class = $this->session->flashdata('feedback_class');
  ?>
 <div class="col-lg-6 col-lg-offset-3">
   <div class="alert alert-dismissible <?= $feedback_class ?>">
      <button type="button" class="close" data-dismiss="alert">&times;</button>
      <p><?= $feedback ?></p>
    </div>
 </div>
   <?php endif; ?>
 <div class="cotainer-fluid">
        <div class="col-lg-6 col-lg-offset-3">
         <?php echo form_open('courses/input',['class'=>'form-group']); ?>
            <br>
  <?php echo form_input(['name'=>'rollno','class'=>'form-control','placeholder'=>'Enter Student ROll NO']); ?>
            <br>
            <select name="group" class="form-control"     onchange="/courses/getsubject'+this.value" >
                <option value="Arts">Arts</option>
                <option value="Science">Science</option>
                <option value="IT">IT</option>
            </select>

            <br>
            <?php echo form_dropdown(''); ?>
            <br>
            <?php echo form_submit(['class'=>'form-control btn btn-         success','value'=>'Submit']) ?>
        <?php echo form_close(); ?>
    </div>
 </div>
 </body>

And This is Controller

   <?php
class Courses extends MY_Controller
  {
public function assign()
{
    $this->load->helper('form');
    $this->load->view('admin/course');
}
public function getsubject($grp)
{
        $this->load->model('courses');
$grp = $this->courses->getsubjects($grp);
  }}
     ?>

I didnt know how to do this in Codeigniter,Got helped from google like Ajax trickds but nothing

onChange event should trigger a javascript function. `onchange="/courses/getsubject'+this.value"` need to refer to JS function. Also your controller method doesn´t return anything. I would use jQuery to load the data, ajax calls is easier that way, I think. — jtheman, Jun 16 '16 at 11:41
but how to get this value in the controller ,in the parameters? and then how next dropdown will be updated? — Saad Mirza, Jun 16 '16 at 11:51
What does that even mean?? "Got helped from google like Ajax trickds but nothing" — Jonathan, Jul 31 '21 at 12:46
There would need to be a slash before your `this.value` value is appended to your url path. `onchange="/courses/getsubject/' + this.value`. Also, `cotainer-fluid` is not the same as `container-fluid` — mickmackusa, Aug 01 '21 at 02:11
I recommend [not performing any ajax, but loading all parent-child relationships as data passed from the controller to the view](https://stackoverflow.com/a/34128745/2943403). — mickmackusa, Apr 28 '23 at 01:55

score 0 · Answer 1 · answered Jun 16 '16 at 19:19

Here is an example:

Controller(Index)

<?php

class Index extends CI_Controller {

    public function __construct() {
        parent::__construct();
        $this->load->helper('url_helper');
        $this->load->model('countries_model');
    }

    public function index() {
        $query = $this->db->query('SELECT id,name FROM countries');
        $data['countries'] = $query->result_array();
        $this->load->view('index/index', $data);
    }

    public function cities() {
        $country_id = $this->input->post('country_id');
        $query = $this->db->query('SELECT id,name FROM cities WHERE country_id=' . $country_id);
        $data['cities'] = $query->result_array();
        $this->load->view('index/cities', $data);
        echo $country_id;
    }

}

Model(Countries_model.php)

<?php

class Countries_model extends CI_Model {

    public function __construct() {
        $this->load->database();
    }

}

View(index.php)

<!DOCTYPE html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Dymanic Selects</title>
<script type="text/javascript" src="<?php echo base_url(); ?>js/jquery.js" ></script>

<script type="text/javascript">
$(document).ready(function(){
    $('#sl_countries').change(function(){
            $('#sl_cities').load("<?php echo site_url('index/cities') ?>",{country_id:$(this).val()});
        }); 
});
</script>

</head>
<body>
    <label>Countries</label>
    <select id="sl_countries">
        <?php foreach($countries as $c):?>
        <option value="<?php echo $c['id']?>"><?php echo $c['name']?></option>
        <?php endforeach;?>
    </select>

    <label>Cities</label>
    <select id="sl_cities"></select>
</body>
</html>

View (cities.php)

<?php foreach ($cities as $c): ?>
    <option value="<?php echo $c['id'] ?>"><?php echo $c['name'] ?></option>
<?php endforeach; ?>

To do this I used jquery, so it's easier. It's necessary two views, index.php is the main view and cities.php is the view to show the list of countries.

Source: http://www.lax-soft.tk/index.php/programacion/php-y-jquery/10-combobox-dependiente-con-codeigniter-y-jquery — Alexander Ceballos, Jun 16 '16 at 20:01
Demo: http://www.lax-soft.tk/codeIgnitercbx/, check all countries, some countries don´t have associated cities, or maybe check the configuration of your server — Alexander Ceballos, Jun 19 '16 at 21:25
`query()` shouldn't ever be called from the Controller layer -- this is what the Model is for. — mickmackusa, Jul 31 '21 at 23:27
Also, you should be using placeholders when you pass user input into a sql query for security/stability. Ulimately, ajax calls to the server may be overkill for relatively small volumes of data. In some cases, it is more ideal to create a multidimensional lookup array, pass it to the view, where is is converted to a json object and referenced on `onchange` events. If using ajax, it would be a good idea to cache the response as a json object so that if the user ever re-selects a specific option, then the server is not bothered by a redundant call. — mickmackusa, Jul 31 '21 at 23:42

score 0 · Answer 2 · answered Apr 01 '22 at 04:14

0

just send array and get on view page.

<select id="sl_countries">
        <?php foreach($countries as $c):?>
        <option value="<?php echo $c['id']?>"><?php echo $c['name']?></option>
        <?php endforeach;?>
    </select>

answered Apr 01 '22 at 04:14

Noor Fahad

94
7

Populate Dynamic Dropdowns List in Codeigniter

2 Answers2