Callback function in Codeigniter with multiple parameters during form validation

Question

In Codeigniter:

Here is the callback function that I am using for validation:

public function has_match($password, $username){
    if (0) {
        /         


        

Answer 1

// CALLBACKS

public function check_user(){

    $result = FALSE;

    $username=$this->input->post('username');

    $email=$this->input->post('emailad');

    $dbmember=$this->members->get_members();

    foreach ( $dbmember as $key){

        // condition of username and email  
        if($username==$key && $email==$key){

        if($username == $key->UserName && $email == $key->EmailAddress){
              $this->form_validation->set_message('check_user','already existed!
                      Please check username and email agian.');
              return FALSE;
              break;
            }                

        return TRUE;

        }  
    }