How to replace "Login" button with user name in CodeIgniter

Question

I'm trying to create a universal header for a website built on CodeIgniter, and I'm having trouble figuring out the code that will switch the 'Login' link for the user's name (with a link to the profile page) after the user logs in.

In the controller functions, I've tried the following code:

if(!$this->session->userdata($userSessionVar))
    {
        $data['header_output'] = "<li><a href='" .  base_url() . "index.php/main/login'>Login</a></li>";
    } else 
    {
        $data['header_output'] = $this->session->data('userFirstName');
    }

(I realize this is incomplete, based on my designs, but it's just to test.) $userSessionVar holds the value "logged in" once logged in. Probably not the best way to do that. And that doesn't seem to work (and I pass the $data to the view). I've also tried making a custom function:

function check_login()
{
$CI =& get_instance();

$userSessionVar = 'logged_in';

if( ! $CI->session->userdata($userSessionVar))
{
    return false;
} return true;
}

And then use the true/false return to structure the $header_output variable. None of these seem to work. I'm new to CodeIgniter and have some intermediate level of PHP/HTML/CSS, etc. I'm sure I'm missing something obvious and would appreciate any help, as well as a heads-up on how to avoid including the code in every controller function.

Answer 1

The variable $userSessionVar is only available within the function check_login(), so when you try to use it outside of the function, it will be blank (and therefore useless).

I recommend that you simply use $this->session->userdata('logged_in') and $CI->session->userdata('logged_in') rather than using the variable $userSessionVar to store what appears to be a constant value.

Also, you have an error in your code. You need to replace $this->session->data('userFirstName') with $this->session->userdata('userFirstName')

Here's how I typically deal with user data. First, add auth.php to the models folder:

<?php

class Auth extends Model {
    private $user_data = false;
    function Auth() {
        parent::Model();

        if ($this->input->post('action') == 'login') $this->login();
        else if ($auth_id = $this->session->userdata('auth_id')) {
            $user = // load user data from the database into the variable $user
            if ($user) {
                $this->user_data = $user;
            } else $this->session->unset_userdata('auth_id');
        }
    }
    function login() {
        // process POST, check with database, and then store user_id using
        // $this->session->set_userdata('auth_id', $user_id_here)
    }
    function me() {
        return $this->user_data? (object)$this->user_data : false;
    }
}

?>

Then, auto-load the model. To do this, edit config/autoload.php like so:

$autoload['model'] = array('auth');

Now your IF statement could look like this:

if ($me = $this->me()) $data['header_output'] = $me->userFirstName;
else $data['header_output'] = '<li><a href="'.base_url().'index.php/main/login">Login</a></li>';