How to declare more than one header on PHP

Question

I want to send my users to different pages based on user action. So I made multiple functions at the top of the page like so:

<?php

function one() {
     header("location: pagea.php");
}
function two() {
     header("location: pageb.php");
}
function three() {
     header("location: pagec.php");
}

?>

Of course I get an error because I am re declaring headers. At first I though it was going to be okay since I am containing them inside functions and am calling any one function at a time. But still I get the error. Is there any other way of doing this?

Answer 1

I think you misunderstand what the HTTP header Location does.

The Location header instructs the client to navigate to another page. You cannot send more the one Location header per page.

Also, PHP sends headers right before the first output. Once you output, you cannot specify any more headers (unless you are using Output Buffering).

If you specify the same header twice, by default, header() will replace the previous value with the latest one... For example:

<?php
header('Location: a.php');
header('Location: b.php');
header('Location: c.php');

will redirect the user to c.php, never once passing by a.php or b.php. You can override this behavior by passing a false value to the second parameter (called $replace):

<?php
header('X-Powered-By: MyFrameWork', false);
header('X-Powered-By: MyFrameWork Plugin', false);

The Location header can only be specified once. Sending multiple Location header will not redirect the users to the pages... It will probably confuse the crap out of the UA. Also, understand that the code continues to execute after sending a Location header. So follow that call to header() with an exit. Here is a proper redirect function:

function redirect($page) {
    header('Location: ' . $page);
    exit;
}