Codeigniter - My form validation callback doesn't work - php

Question

I have tried to copy from Codegniter's documentation, but I can't make form validation callbacks working.
I added helper form, url and library form_validation. It's not working and always returns "false"
Controller
public function addtest()
{
$this->load->helper(array('form', 'url'));
$this->load->library('form_validation');
$this->form_validation->set_rules('username', 'Username', 'callback_username_check');
if($_SERVER['REQUEST_METHOD'] == 'POST')
{
if ($this->form_validation->run() == TRUE)
{
die('true');
}
else
{
die('false');
}
}
$this->template
->build('myform',array());
}
public function username_check($str)
{
if ($str == 'test')
{
return TRUE;
}
else
{
return FALSE;
}
}
View
<form method="post" action="" class="form-horizontal form-label-left">
<div class="col-xs-12 col-md-9">
<div class="x_panel">
<div class="form-group col-xs-12">
<div class="col-xs-3">
<label class="control-label">Folder name</label>
</div>
<div class="col-xs-9">
<input type="text" name="username" value="" class="form-control " id="" placeholder="">
</div>
</div>
<button type="submit" class="btn btn-success">Submit</button>
</div>
</div>
</form>

Answer 1

Extend your form_validation library in Libraries.php
MY_Form_validation.php
<?php if (!defined('BASEPATH')) exit('No direct script access allowed');
class MY_Form_validation extends CI_Form_validation
{
function run($module = '', $group = '') {
(is_object($module)) AND $this->CI =& $module;
return parent::run($group);
}
}
/* End of file MY_Form_validation.php */
/* Location: ./application/libraries/MY_Form_validation.php */

Answer 2

My Controller function is like this and it runs perfectly. I have autoloaded all libraries
public function change_password()
{
if($this->isLoggedin()){
$data['title']='Change Password';
if($_POST)
{
$config=array(
array(
'field' => 'old_password',
'label' => 'Old Password',
'rules' => 'trim|required|callback_checkPassword'
),
array(
'field' => 'password',
'label' => 'Password',
'rules' => 'trim|required'
),
array(
'field' => 'conf_password',
'label' => 'Confirm Password',
'rules' => 'trim|required|matches[password]'
)
);
$this->form_validation->set_rules($config);
if ($this->form_validation->run() == false)
{
// if validation has errors, save those errors in variable and send it to view
$data['errors'] = validation_errors();
$this->load->view('change_password',$data);
}
else
{
// if validation passes, check for user credentials from database
$this->Login_model->updatePassword($_POST['password'],$this->session->userdata['id']);
$this->session->set_flashdata('log_success','Congratulations! Password Changed');
redirect(base_url() . 'Login/dashboard');
}
}
else
{
$this->load->view('change_password',$data);
}
}
else
{
redirect(base_url().'Login');
}
}
public function checkPassword($str)
{
$check=$this->Login_model->checkPassword($str);
if($check)
{
return true;
}
else
{
$this->form_validation->set_message('checkPassword', 'The Current Password you have provided is incorrect');
return false;
}
}

Answer 3

In HTML (Add ID field)
<input type="text" name="username" value="" class="form-control " id="username" placeholder="">
<button type="submit" class="btn btn-success" id="submit">Submit</button>
In your AJAX code
<script type="text/javascript">
$(function(){
$( "#submit" ).click(function(event)
{
event.preventDefault();
var username= $("#username").username();
$.ajax(
{
type:"post",
url: "<?php echo base_url(); ?>index.php/controller/Method",
data:{ username:username},
success:function(res)
{
}
});
});
});
</script>>
In Controller
No need of check if($_SERVER['REQUEST_METHOD'] == 'POST') because it comes through it always
public function addtest()
{
$this->load->helper(array('form', 'url'));
$this->load->library('form_validation');
$this->form_validation->set_rules('username', 'Username', 'callback_username_check');
if ($this->form_validation->run() == TRUE)
{
die('true');
}
else
{
die('false');
}
$this->template->build('myform',array());
}
public function username_check($str)
{
if (empty($str))
{
echo "Empty";
}
else
{
if ($str == 'test')
{
return TRUE;
}
else
{
return FALSE;
}
}
}
Check more about CodeIgniter callback function