Why is my SESSION array OK on one page but empty on another?

Question

Hi,

I have a class that sets various session variables. After I set the session variable I do a var dump of SESSION and get an output of them all. all good so far. Then I navigate to another page.

session_start(); // i call this right after opening the php tag
var_dump($_SESSION); // i call this after setting the variables

and it's empty this time?

Setting my sessions

while( $row = sqlsrv_fetch_array( $stmt, SQLSRV_FETCH_ASSOC))
    {
           $_SESSION['atid'] = $row['autotaskid'];
           $_SESSION['bmsid'] = $row['bmsid'];
           $_SESSION['shavlikid'] = $row['shavlikid'];
           $_SESSION['cpid'] = $row['cpid'];
    }

Trying to use the variables on another page

$autotaskid = $_SESSION['atid'];
    $tsql = "SELECT COUNT(tblBackupArchive.StatusID) AS total, tblBackupArchive.StatusID ".
            "FROM tblBackupArchive INNER JOIN ".
            "tblBackup ON tblBackupArchive.BackupID = tblBackup.BackupID ".
            "GROUP BY tblBackupArchive.StatusID, tblBackup.ClientID ".
            "HAVING (tblBackup.ClientID = " . $autotaskid . ")";    

Results in

Undefined index: atid in C:\Program File...

I've made sure I'm issuing the start_session(); function before any other code is run on every page that uses them.

Another important point: the php page that calls the method setting the variables within an iframe. when i open the page in a new tab/window it sets the sessions correctly. It's almost like the main window has session variables and then each iframe keeps it own seperate.

Any ideas?

Billy

Answer 1

Based on your first code block, it sounds like you might be calling session_start() after you've tried to set the $_SESSION variables. You must call session_start() first! I could be wrong, in which case I apologise. But based on the above code snippet it could well be your problem!

Answer 2

If you're calling session_close() where you should be, then are you accidentally destroying the session? Perhaps a few too many session_destroy() calls?

And by a few too many I mean one.

Answer 3

Any ideas?

Yes. You have to learn to debug your code.
As you can see, your question cannot be answered out of guesswork. So, it's time for handwork.

• First make sure you can see any error occurred. Just add an intentional one and see. If you see no errors you have to turn it on.

• then make a testing script to see if your sessions do work

  <? 
  session_start(); 
  if (!isset($_SESSION['counter'])) $_SESSION['counter']=0;
  echo "Refreshed ".$_SESSION['counter']++." times.<br>
  <a href=".$_SERVER['PHP_SELF'].'?'.session_name().'='.session_id().">refresh</a>"; 
  ?>
  

if it works, make it to use cookies

<? 
session_start(); 
if (!isset($_SESSION['counter'])) $_SESSION['counter']=0;
echo "Refreshed ".$_SESSION['counter']++." times.<br>
<a href=".$_SERVER['PHP_SELF'].">refresh</a>"; 
?>

if it works too, you have to check your code.
Print out variables, reduce code, etc