Codeigniter Unique表单验证

<?php if (!defined('BASEPATH')) exit('No direct script access allowed');

class MY_Form_validation extends CI_Form_validation
{
    function __construct($rules = array())
    {
        parent::__construct($rules);
    }

    function unique($value, $params)
    {
        $CI =& get_instance();
        $CI->load->database();
        $CI->form_validation->set_message('unique', '%s 已经存在.');

        $parts = explode('.', $params);

        $table = $parts[0];
        $column = $parts[1];
        $id_column = (isset($parts[2])) ? $parts[2] : '';
        $id = (isset($parts[3])) ? $parts[3] : (($id_column) ? $id_column : '');

        $CI->db->where($column, $value);

        if ($id_column && $id && isset($_POST[$id]) && $_POST[$id])
        {
            $CI->db->where("$id_column <>", $_POST[$id]);
        }

        return ($CI->db->count_all_results($table) > 0) ? FALSE : TRUE;
    }
}
// END MY_Form_validation Class

/* End of file MY_Form_validation.php */
/* Location: ./application/libraries/MY_Form_validation.php */

end