CodeIgniter - How to work with sessions correctly?

Question

CodeIgniter

In the autoload.php file, I set the session class to autoload.
Now I'm trying to get the session ID:

$session_id = $this->session->userdata('session_id');
echo $session_id;

I receive nothing. Emptiness.
If you do a var_dump, it returns NULL.
Own data can be written to the session and read from it, but the provided ones cannot.
What am I doing wrong? Tell me please.

Answer 1

The method $this->session->userdata()returns the data that you saved earlier.
To get the session ID, use either session_id(), or $this->session->session_id(it refers to session_id()).
Personally, I would use it $this->session->session_id, because it can be adjusted to fit your needs if that.