How to save and extract session data in codeigniter

Question

I save some data in session on my verify controller then I extract this session data into user_activity model and insert session data into activity table. My problem is only

Answer 1

initialize the Session class in the constructor of controller using

$this->load->library('session');

for example :

 function __construct()
   {
    parent::__construct();
    $this->load->model('user','',TRUE);
    $this->load->model('user_activity','',TRUE);
    $this->load->library('session');
   }