Question

I’m working on a messaging system and want the user’s userid to be posted to the database along with the message. Right now, the message is posting to the database, but with a user ID of 0.

How can I get the user ID from the session data to post to the database along with the message? Sidenote: I’m using Tank Auth for authentication. (From the mysql side, user_id in the message table is a foreign key referencing id in the users table).

Controller

function index() {

    if ($this->input->post('submit')) {
            $id = $this->input->post('user_id');
            $message = $this->input->post('message');

            $this->load->model('message_model');
            $this->message_model->addPost($id, $message);
        }
    }   

Model

function addMessage($id, $message) {
        $data = array(
            'user_id' => $id,
            'message' => $message
        );

        $this->db->insert('message', $data);
    }

Answer 1

Taken directly from CI’s documentation:

Retrieving Session Data

Any piece of information from the session array is available using the
following function:

$this->session->userdata('item');

Where item is the array index
corresponding to the item you wish to fetch. For example, to fetch the
session ID you will do this:

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

Note: The
function returns FALSE (boolean) if the item you are trying to access
does not exist.

So, if you have a piece of session data named user_id, you would access it like this:

$user_id = $this->session->userdata('user_id');