为什么此页面不重定向？

Question

我在php中重定向页面时遇到问题。

<?php           
        include '../include/dbfunctions.php';
        $email = $password = "";
        $err = "";
        if ($_SERVER["REQUEST_METHOD"] == "POST") {
            if (isset($_POST['login']) && !empty($_POST['password'])) {

                $email = trim($_POST['email']);
                $password = trim($_POST['password']);

                $link = get_db_connection();


                if (mysqli_connect_errno()) {
                    die(" Something went wrong ! ");
                }

                $user_email = mysqli_real_escape_string($link, $email);
                $user_password = mysqli_real_escape_string($link, $password);

                $query = "SELECT  username FROM user WHERE user_email = '$user_email' AND user_password = SHA1('$user_password') AND user_active = '1';";
                $data = mysqli_query($link, $query);

                if (mysqli_num_rows($data) == 1) {

                    $row = mysqli_fetch_array($data);

                    $username = $row['username'];
                    mysqli_close($link);
                    if (!empty($username)) {

                        header('location:http://www.xxxxxxxxxxxxxx.be/login/dashboard.php');
                        exit();
                    }
                } else {
                    $err = "Invalid combination of e-mail and password";
                    echo $err;
                }
            } else {

            }
        }
        ?>

我不知道。 如果我填写了无效的密码或电子邮件，则会收到错误消息。 但是，当它们正确时，什么也不会发生。

Answer 1

if (!empty($username)) {
              header('location:http://www.xxxxxxxxxxxxxx.be/login/dashboard.php');
                    exit();}

$username可能为空。

Answer 2

if (!empty($username)) {
     header('location:http://www.yoursite.be/login/dashboard.php?error=error in login please try agine');
     exit();
}