Question

Im writing a login script. My db.php doesnt echo/print anything so why doesnt header(“Location: index.php”); redirect upon successful login? the login info is correct. I know i need to sanitize the input but that is not a problem at the moment.

 <?php
        require('db.php');
        $username = $_POST['un'];
        $password = $_POST['pw'];
        $qry="SELECT uid FROM users WHERE name='$username' AND pass='".md5($password)."'";
        $result=mysql_query($qry);
        if(mysql_num_rows($result) == 1){
            session_regenerate_id();
            $user = mysql_fetch_assoc($result);
            $_SESSION['S_UID'] = $user['uid'];
            session_write_close();
            header("Location: index.php");
            exit();
        }else{
            echo "<center><form action='index.php' name='login'>Login failed! Please try again with correct username and password.<br><input type='submit' name='failed' value='Return to Login'></form></center>";
            exit();
        }
    ?>

Answer 1

the function header will only work if no output has been sent by the script before the function is called. Check if any codes above has echoed something.

If not, check that the include files above do not have an extra space or newline after the closing “?>” tag. Otherwise this space or newline will be sent to the browser before your header.