storing logged in users user_id on page

[Cflax]

Hello all...fairly new to this php/mysql thing... working on my final project thats due in about 24 hours... and i hit a rut...
im making a pretty basic, online classifieds site. users can sign up, login, post new listings and view others listings by clicking on different categories. the problem i am having right now is this...When the user clicks on "My listings" i need it to pull only the listings that were created by that users user_id, which is the primary key in my user_info table...my professor suggested storing it in hidden field through the login submit button...very confused and frustrated... any help is much appreciated...

[dagon]

Cflax;10969616 wrote:

my professor suggested storing it in hidden field through the login submit button

either that or use a session.

[Res]

Expanding on what dagon said; when you authenticate the user, you will want to store the user_id inside the $_SESSION superglobal. Session variables persist with the user from page to page.

$_SESSION['user']['user_id'] = $user_id;
$_SESSION['user']['user_name'] = $user_name;

This allows you to access the information for that user at any time.

echo "Logged in as ".$_SESSION['user']['user_name']."<br/>";