动态依赖下拉CodeIgniter Ajax不起作用

Question

I'm trying to populate the second dropdown base on the first dropdown using ajax in codeigniter but it seems not it's not populating nor displaying the alert error in my ajax, it does nothing. Is there anything I miss or typo? thank you very much.

My View

<select name="carbrand" class="form-control" required="true" id="carbrand">
<option value="" selected disabled>--- Select Car Brand ---</option>
<li role="separator" class="divider"></li>
                        <?php
                        foreach($groups as $row){
                        echo '<option value="'.$row->brand.'" >'.$row->brand.'</option>';
                                }
                                ?>

   </select>
   </div>
   //SECOND DROPDOWN
   <div class="form-group">
   <select name="carmodel" class="form-control" id="carmodel" disabled="">
   <option value="" selected disabled>--- Select Car Model ---</option>
   </select>

   //SCRIPT
   <script>
   $(document).ready(function(){
   $('#carbrand').on('change', function(){
    var carbrand = $(this).val();
    if(carbrand == '')
    {
      $('#carmodel').prop('disabled', true);
    }
    else
    {
      $('#carmodel').prop('disabled', false);
      $.ajax({
        url:"<?php echo base_url() ?>/quote_aia/get_models",
        type:"POST",
        data:{'carbrand' : carbrand },
        dataType: 'json',

        success: function(data)
        {
          $('#carmodel').html(data);
        },
        error:function()
        {
          alert('Error');
        }
      });
    }
   });
 });

My Controller

     public function get_models()
     {  
    $this->load->model('quote'); 
    $carbrand = $this->input->post('carbrand');
    $brand = $this->quote->get_model_query($carbrand);
    if(count($brand)>0)
    {
        $cb_select = '';
        $cb_select .='<option value="">Select Model </option>';
        foreach ($brand as $brando) {
            $cb_select .='<option value="'.$brando->model.'"> '.$brando->model.'</option>';
        }
        echo json_encode($cb_select);
    }
}

My Model

 public function get_model_query($carbrand)
{
    $query = $this->db->get_where('tbl_fmv', array('brand' => $carbrand));
    return $query->result();
}

Please help me thankyou very much

Answer 1

立即修复，我只是重新编码，不知道我错过了什么，但已修复