Question

I get an undefiend variable error when i call another $_SESSION but when i remove this piece of code it shows no errors, I am using $_SESSION in order to pass one variable to another php script, can anyone enlighten me on what may be causing this issue?

I know the variable is defiened but for some reason calling a $_SESSION causes this error?

<div>
    <? 
    if(empty($item_details['trucks'])) {
        include_once ('trucks.php');
        $_SESSION['runmapapi'] = 'start'; 
        //$runmapapi == true;
        echo '<p> Success</p></div>'; 
    } else {
        echo '<p>failed</p></div>';
    } 
    ?>
<div>
    <p>Cars</p>
</div>  
</div>
</div></body>
<? } ?>
<? } ?>   
<?= $print_footer; ?>

Answer 1

when you are using session variable, you have to initialize the session by using

session_start();

so wherever you use any of the session variable in your page, make sure you first declare the session_start()

so in your page it should be

//initialize session to use session variable
session_start();
include_once ('trucks.php');
$_SESSION['runmapapi'] = 'start';