用于在页面之间保存变量的会话

Question

I'm making a logoquiz for my Computer Science class, and I'm busy with a page to register users with an account name and email address. After successfully registering people will be redirected to index.php

In the page the are redirected to, there is a green box which says that the registration finished, and gives them further instructions.

When testing, every time I visit index.php, it gives that notice with nothing in the email and username.

<!--- Notice itself --->
<?php
    session_start();
    if(isset($_SESSION)){
        $email = $_SESSION["email"];
        $username = $_SESSION["username"];
    ?>
<!--- Green box that pops up --->
        <div class="notice success"><i class="icon-ok icon-large"></i> Je registratie is succesvol verzonden <?php echo $username;?><br>
        Er is een email verzonden naar <?php echo $email; ?>.<br>
        Volg de instucties in deze mail om te kunnen beginnen<a href="#close" class="icon-remove"></a></div>

        <?php 
        session_destroy();
        } ?>

In the register page itself (RegSpelers.php), this code is used for the session

<?php }elseif($wrong == FALSE && !empty($_POST)){
    // After checking for wrong entered field or nothing at all use session.
    $_SESSION["email"] = $email;
    $_SESSION["username"] = $username;
    header ('Location: index.php');
    } ?>

Answer 1

Because of

session_start();

The $_SESSION array exists and isset return true.

Now maybe this is what you where looking for

if(isset($_SESSION['email'])){