Increment session variable by one

Question

How the heck do I increment a variable that's inside a session? If I declare $attempt, each time a user unsuccessfully attempts to login, I want $attempt to increase by 1. In the event it gets to 3, display a captcha.

This doesn't seem to work. :-P

$this->session->set_userdata('attempt',$this->attempt++);

Answer 1

$attempt = $this->session->userdata('attempt');
$attempt++;
$this->session->set_userdata('attempt', $attempt);

Answer 2

hi all this doesn't work for me too :

$attempt = $this->session->userdata('attempt');
++$attempt;
$this->session->set_userdata('attempt', $attempt);