is_unique for codeigniter form validation

Question

I\'m trying to figure out how I can use the is_unique rule from the Codeigniter form validation library in the following situation.

I\'m trying to submi

Answer 1

Extend Form_validation.php library create class inside of application/libraries file name MY_Form_validation.php

ci =& get_instance();
        }

                public function is_unique_update($str, $field){
                $explode=explode('@', $field);
                $field_name=$explode['0'];
                $field_id_key=$explode['1'];
                $field_id_value=$explode['2'];
                sscanf($field_name, '%[^.].%[^.]', $table, $field_name);

                 if(isset($this->ci->db)){
                        if($this->ci->db->limit(1)->get_where($table, array($field_name => $str,$field_id_key=>$field_id_value))->num_rows() === 0){
                             $this->ci->form_validation->set_message('is_unique_update', 'The {field} field must contain a unique value.');
                            return false;
                        }
                        return true;
                    }


            }
}  

Now in your controller

$this->form_validation->set_rules('user_name', 'User Name', 'required|trim|xss_clean|is_unique_update[users.user_name@id@'.$id.']');  

"@" I used for explode the string
where id is primary key of users table
and $id is the value of id. Now you can use this is_unique_update validation in any controller.