选择组合框代码生成器时，如何向表中显示数据

I've made a combobox based on the database. I want when I've selected one combobox and instantly display the appropriate table combobox that I choose. Example when I choose west java table will show bandung and bogor.

this my controller

public function show() {
    $data['provinsi'] = $this->mdl_onchange->get_provinsi();
    $data['kota'] = $this->mdl_onchange->get_kota();
    $this->load->view('form_onchange', $data);
}

this my model

function get_provinsi() {
    $query = $this->db->get('table_provinsi');
    return $query->result();
}

function get_kota() {
    $query = $this->db->get('table_kota');
    return $query->result();
}

this is my view

<p>
    <label for="select_provinsi"></label>
    <select name="select_provinsi" id="select_provinsi">
        <option>--Pilih Provinsi--</option>

        <?php foreach($provinsi as $row_provinsi)   {   ?>
            <option value="<?php echo $row_provinsi->id_provinsi?>">
                <?php echo $row_provinsi->nama_provinsi; ?>    
            </option>
        <?php } ?>
    </select>
</p>
<table border="1" name="select_kota" id="select_kota" style="border-
      collapse:collapse; width:60%;">
    <tr style="background:yellow;">
        <th>Id kota</th>
        <th>Id provinsi</th>
        <th>nama kota</th>
    </tr>
    <?php foreach($kota as $c){?>
        <tr>
            <td>
                <?php echo $c->id_kota; ?>
            </td>
            <td>
                <?php echo $c->id_provinsi; ?>
            </td>
            <td>
                <?php echo $c->nama_kota; ?>
            </td>
        </tr>
    <?php } ?>
</table>

my jquery

<script type ="text/javascript">
    $("#select_kota").chained("#select_provinsi");
</script>

I've made like this but its data always appear when I have not chosen combobox western Java. it is

I see you are using chained Jquery. That's for chaining two selects, not for a table.

For this, the best approach you could get is to perform an Ajax call to get the table rows and modify the table tbody inner HTML.

First, you need to modify the model get_kota() function, to select only the kota on a provinsi, by it's id_provinsi:

function get_kota($id_provinsi) {
    $this->db->where('id_provinsi', $id_provinsi);
    $query = $this->db->get('table_kota');
    return $query->result();
}

After that, create a new function on your controller to return the new values via Ajax. Here I'll include also the modification to the original method to remove the first call for kotas:

public function show() {
    $data['provinsi'] = $this->mdl_onchange->get_provinsi();
    $this->load->view('form_onchange', $data);
}

public function ajax_getkotas($id_provinsi) {
    $kotas = $this->mdl_onchange->get_kota($id_provinsi);

    foreach ($kotas as $kota) {
       echo '<tr>
';
           echo '<td>' . $kota->id_kota . '</td><td>' . $kota->id_provinsi . '</td><td>' . $kota->nama_kota . '</td>
';
       echo '</tr>
';
    }
}

Now, let's go back to your view. Let's divide it into three parts: the select, the table and the jquery.

You can keep your select as it is right now.

The table will be empty at first, you can maybe have something like this:

<table border="1" name="select_kota" id="select_kota" style="border-
      collapse:collapse; width:60%;">
    <thead>
        <tr style="background:yellow;">
            <th>Id kota</th>
            <th>Id provinsi</th>
            <th>nama kota</th>
        </tr>
    </thead>
    <tbody>
         <tr><td>Please, select a provinsi from the above dropdown to display results</td></tr>
    </tbody>
</table>

And now let's go for the JQuery Ajax call:

$('#select_provinsi').on('change', function() {
  $.ajax({
        type: 'GET',
        url: "<?php echo site_url('your_controllername/ajax_getkotas') ?>" + "/" + $('#select_provinsi').val() , // we call our new function with the selected id
        dataType: "html",
        success: function (data) { // change the data from our response
            $('#select_kota tbody').html(data); //rows are printed inside the tbody of our table
        },
        failure: function(err) {console.log("Error on the Ajax call");} // Some error feedback just in case. You can check network XHR to see what's going on.
    });
})

With this I think you can get it working. Let me now it that's works for you or we need to change anything.