在同一个函数中销毁和创建会话

Question

in my logout function i like to destroy all session except one here is my function :

    public function out(){

    $ref = $this->session->userdata('ref'); 
    var_dump($ref);

    $this->session->sess_destroy();

    $this->session->set_userdata('ref', $ref ); 


    $ref = $this->session->userdata('ref'); 
    echo '---------------------------------------<br />';
    var_dump($ref);


    }

but this doesnt work and it destroys all the session even ref and when i check ref in the next page i get null

inn the function page i get this output :

array (size=2)
  'val' => int 666
  'date' => int 1397060477

---------------------------------------

array (size=2)
  'val' => int 666
  'date' => int 1397060477

A PHP Error was encountered

Severity: Notice

Message: Undefined index: last_activity

Filename: drivers/Session_cookie.php

Line Number: 590

Backtrace:

A PHP Error was encountered

Severity: Notice

Message: Undefined index: session_id

Filename: drivers/Session_cookie.php

Line Number: 611

Backtrace: 

im using 3.0-dev

Answer 1

Try this:

public function out(){

    $ref = $this->session->userdata('ref'); 
    $this->session->sess_destroy(); // this kills the ID/cookie

    $this->session->sess_create(); // properly start a new session with new ID/cookie

    if($ref)        
    $this->session->set_userdata('ref', $ref ); 

     redirect(base_url().'index');  

}

Note:

sess_create() is not documented here: CodeIgniter Sessions

You have to look at /system/libraries/Session.php to find sess_create()

UPDATE

When using Dev 3.0 then you need to do this:

$this->session->__construct();