Call to undefined method CI_Input::get_cookie() - Code Igniter

I'm trying to make a call to the get_cookie() method from the input library but I am receiving this error.

"Fatal error: Call to undefined method CI_Input::get_cookie() "

I've loaded the helper for cookie and have used the call set_cookie() in the parent function. I'm not sure if this should be an issue.

Here is the code that is creating the error.

    class Main extends MY_Controller
    {
        function __construct()
        {
            parent::__construct();

            //load library
            $this->load->helper('cookie');

            echo "Welcome controller<br>";

        }

        function index()
        {   


            //get platform cookie
            $_platform = $this->input->get_cookie('platform'); //<-ERROR

           开发者_Go百科 if (!$this->tank_auth->is_logged_in()) {
                redirect('/auth/login/');
            } else {
                $data['user_id']    = $this->tank_auth->get_user_id();
                $data['username']   = $this->tank_auth->get_username();
                $data['platform']   = $_platform['value'];
                $this->load->view('welcome', $data);
            }
        }
    }

Since you’ve loaded the cookie helper, you can just fetch the cookie with a function.

$_platform = get_cookie('platform'); 

And if I recall correctly, getting the cookie via Input class is like this:

$_platform = $this->input->cookie('platform'); 

http://codeigniter.com/forums/viewthread/181572/#867911