PHP Header Redirect problem (no, not that common problem)

PHPredirect

Firstly, this is not the headers already sent' problem.

I have an include file, that does the redirect. This works on every server I have tried it on except the production server, which runs windows.

When I run it on the production server, it only redirects the include file, not the entire page.

I have the main file, index.php:

<?php include('red.php'); ?>
<html ....
>

And I do the redirect to another page in red.php. Then the redirected page will show up at the top of the index.php page, with the rest of the index.php html file after this page.

Have the mess up some setting in php.ini?

After some more investigation, the problem is when I use a full URL rather than a relative URL. The first will only redirect the included file. (the problem I discovered above)

while the second works correctly

red2.php:



header("Location: http://example.com/newfile.php");
    header("Location: newfile.php");'

Best Answer

When I run it on the production server, it only redirects the include file, not the entire page.

That's a funny thing to say because it's not really possible. Only a single blob of data is presented to the browser you can't "redirect" part of it but you can include from multiple files in order to produce a composite blob.

Perhaps, this is what you're doing. Perhaps you're doing an include instead of a redirect. Remember a redirect is done like this:

header('Location: file.php');
exit;

The exit at the end is recommended so execution doesn't continue unnecessarily.

1. Basic answer

You can use the header() function to send a new HTTP header, but this must be sent to the browser before any HTML or text (so before the <!DOCTYPE ...> declaration, for example).

header('Location: '.$newURL);

2. Important details

die() or exit()

header("Location: http://example.com/myOtherPage.php");
die();

Why you should use die() or exit(): The Daily WTF

Absolute or relative URL

Since June 2014 both absolute and relative URLs can be used. See RFC 7231 which had replaced the old RFC 2616, where only absolute URLs were allowed.

Status Codes

PHP's "Location"-header still uses the HTTP 302-redirect code, this is a "temporary" redirect and may not be the one you should use. You should consider either 301 (permanent redirect) or 303 (other).

Note: W3C mentions that the 303-header is incompatible with "many pre-HTTP/1.1 user agents. Currently used browsers are all HTTP/1.1 user agents. This is not true for many other user agents like spiders and robots.

3. Documentation

HTTP Headers and the header() function in PHP

4. Alternatives

You may use the alternative method of http_redirect($url); which needs the PECL package pecl to be installed.

5. Helper Functions

This function doesn't incorporate the 303 status code:

function Redirect($url, $permanent = false)
{
    header('Location: ' . $url, true, $permanent ? 301 : 302);

    exit();
}

Redirect('http://example.com/', false);

This is more flexible:

function redirect($url, $statusCode = 303)
{
   header('Location: ' . $url, true, $statusCode);
   die();
}

6. Workaround

As mentioned header() redirects only work before anything is written out. They usually fail if invoked inmidst HTML output. Then you might use a HTML header workaround (not very professional!) like:

 <meta http-equiv="refresh" content="0;url=finalpage.html">

Or a JavaScript redirect even.

window.location.replace("http://example.com/");

Javascript – Redirecting to a relative URL in JavaScript

You can do a relative redirect:

window.location.href = '../'; //one level up

window.location.href = '/path'; //relative to domain