How do check if a PHP session is empty?

Question

Is this bad practice?

if ($_SESSION['something'] == '') {     echo 'the session is empty'; } 

Is there a way to check if its empty or it is not set? I'm actualy doing this:

if (($_SESSION['something'] == '') || (!isset($_SESSION['something'])) {     echo 'the session is either empty or doesn\'t exist'; } 

Does !isset just checks if a $_SESSION[''] exist and doesn't check if, is there are values in the array or not

Answer 1

I would use isset and empty:

session_start(); if(isset($_SESSION['blah']) && !empty($_SESSION['blah'])) {    echo 'Set and not empty, and no undefined index error!'; } 

array_key_exists is a nice alternative to using isset to check for keys:

session_start(); if(array_key_exists('blah',$_SESSION) && !empty($_SESSION['blah'])) {     echo 'Set and not empty, and no undefined index error!'; } 

Make sure you're calling session_start before reading from or writing to the session array.