笨：依赖下拉菜单无法正常工作

Question

我的控制器： -

<?php if (! defined('BASEPATH')) exit('No direct script access allowed'); 
class Cnewincident extends CI_Controller 
{  
    public function __construct() 
    { 
     parent::__construct();   
     $this->load->database(); 
    } 
    public function index() 
    {    
     $this->load->model('users/supervisor/Mnewincident'); 
     $data['category'] = $this->Mnewincident->getCatgories(); 
     //loads up the view with the query results 
     $this->load->view('users/supervisor/vnewincident',$data); 

     if($this->input->post('addrequest')) 
     {     
      $this->load->model('users/supervisor/Mnewincident'); 
      // to get the username from table who is creating this request 
      $session_data = $this->session->userdata('emailid'); 
      $firstname = $this->Mnewincident->get_firstname($session_data); 

      // passing that usename in newincident table 
      if($this->Mnewincident->add_request($firstname)) 
      { 
       $this->session->set_flashdata('message', 'Request added successfully.'); 
       redirect('users/supervisor/Cnewincident'); 
      } 
      else 
      { 
       $this->session->set_flashdata('message', 'Failed to add the request. Try again'); 
       redirect('users/supervisor/Cnewincident'); 
      } 
     } 
    } 
    //call to fill the second dropdown with the subcategories 
     public function loadsubcat() 
     { 
      echo $category_id = $this->input->post('id',TRUE); 
      $subcatData['subcatDrop']=$this->Mnewincident->getSubcatgories($category_id); 
      $output = null; 
      foreach ($subcatData['subcatDrop'] as $row) 
      { 
       $output .= "<option value='".$row->subcategory_description."'>".$row->subcategory_description."</option>"; 
      } 
      echo $output; 
     } 
} 

?> 

我的模型： -

class Mnewincident extends CI_Model 
{ 
    public function __construct() 
    { 
     $this->load->database(); 
    } 

     public function getCatgories() 
     { 
      $this->db->select('category_id,category_description'); 
      $this->db->from('tbl_categorymaster'); 
      $query = $this->db->get(); 
      foreach($query->result_array() as $row) 
      { 
      $data[$row['category_id']]=$row['category_description']; 
      } 
      return $data; 
     } 

     public function getSubcatgories($category_id=string) 
     { 
      $this->db->select('srno,subcategory_description'); 
      $this->db->from('tbl_subcategorymaster'); 
      $this->db->where('category_id',$category_id); 
      $query = $this->db->get(); 
      return $query->result(); 
     } 
} 

我的视图代码： -

   $(document).ready(function() { 
       $("#category").change(function(){      
       $.ajax({ 
        url:"<?php echo base_url()."users/supervisor/Cnewincident/loadsubcat"?>", 
        data: {id:$(this).val()}, 
        type: "POST", 
        success:function(data){ 
        $("#subcategory").html(data); 
       } 
       }); 
      }); 
     }); 

Answer 1

1.Remove the echo from loadsubcat() 

public function loadsubcat() 
{ 
**echo** $category_id = $this->input->post('id',TRUE); 
.......... 
................. 
} 

希望它有效.....