PHP Store User Data without Sessions

Is there anyway to store users data such as userid, email, etc to be accessible from all pages of a website after they have logged in, but without using sessions or cookies?

For example:

class User
{
  var $userid;
  var $username;
  var $email;

  .. methods..
}

after they login at login.php

$currentUser = new User($_POST['username'])

now, how do I access $currentUser from another page, such as index.php if I shouldn’t use sessions or cookies at all?

so that I could do the following in index.php:

if ($currentUser->userid > -1)
{
  echo "you are logged in as: " . $currentUser->username;
}
else
{
  echo "click here to login";
}

i asked a similar question before, here, but the answers didn’t fulfill my needs.

Answer

If you’re over-the-top gung-ho with regards to OOP and refuse to directly interact with sessions/cookies, I’d strongly suggest you simply encapsulate sessions instead of remaking them. Even something as simple as this:

//oopsess.php
<?php
    class Session{
        ...
    }

    session_start();

    function getSession(){
        //return the session if one exists
        if (isset($_SESSION['sessionObject']))
            return $_SESSION['sessionObject'];

        //otherwise save and return a new one
        $_SESSION['sessionObject']=new Session();
        return $_SESSION['sessionObject'];
    }
?>

Easily adaptable if you want to store the data clientside – in a cookie – instead of just storing the session id client side (which is what this does).

Edit: Also, teasing aside with regards to OOP, if your code is all very OOP, this is actually a genuinely good way to keep your code clean – not just a way to satisfy your OOP-hungry cravings as I implied above 😉