Very useful thanks,

However you stated that including the validation callbacks in your controllers/models looked messy. I agree with this but I don’t extend the form_validation library, I just create a form_validation helper that contains all the additional callback functions.

I know both ways are valid, but its always nice to have more than one way to achieve a task :D

Script is way better that I used before, but now I faced a problem, that my register form does not show a message which I set. I t works, but message does not appear. My script:

<?php if (!defined('BASEPATH')) exit('No direct script access allowed');
/**
* MY_Form_validation Class
*
* Extends Form_Validation library
*
* Adds one validation rule, "email_check" and accepts a
* parameter, the name of the table and column that
* you are checking, specified in the forum table.column
*
* Note that this update should be used with the
* form_validation library introduced in CI 1.7.0
*/
class MY_Form_validation extends CI_Form_validation {

function __construct()
{
parent::__construct();
}

// ——————————————————————–

/**
* Email_check
*
* @access public
* @param string
* @param field
* @return bool
*/

function email_check($str, $field)
{
$CI =& get_instance();
list($table, $column) = explode(‘.’, $field, 2);

$CI->form_validation->set_message(‘email_check’, ‘The %s that you requested is already in use.’);

$query = $CI->db->query(“SELECT COUNT(*) AS dupe FROM $table WHERE $column = ‘$str’”);
$row = $query->row();
return ($row->dupe > 0) ? FALSE : TRUE;
}
}
?>

And I used:
$this->my_form_validation->set_rules(‘email_address’, ‘Email Address’, ‘email_check[reg_users.email]‘);

I did it this way, because your exact code did not worked. I use 2.x version

ALTER TABLE users ADD UNIQUE INDEX(firstname, lastname);

works after its placed in:
“application\libraries”

i added the My_Form_validation to libraries that looks like this http://pastebin.com/YWnMu6fe

my form validation looks like this:
$this->form_validation->set_rules(‘username’, ‘Username’, ‘required|min_length[4]|unique[members.username]‘);

but the username still gets inserted with a dupe. Can someone help?

By the way well done, I hope anyone can guide me to solve it.

//OLD
class MY_Form_validation extends CI_Form_validation {

function __construct()
{
parent::__construct();
}
}

//NEW
class MY_Form_validation extends CI_Form_validation {

function __construct($rules = array())
{
parent::__construct();
$this->_config_rules = $rules;
}
}

Very useful and clean function!
Thank you for sharing this!