Question

On various pages throughout my PHP web site and in various nested directories I want to include a specific file at a path relative to the root.

What single command can I put on both of these pages…

http://www.example.com/pageone.php

http://www.example.com/somedirectory/pagetwo.php

…to include this page:

http://www.example.com/includes/analytics.php

This does not work:

<?php include('/includes/analytics.php'); ?> 

Does it matter that this is hosted in IIS on Windows?

Answer 1

If you give include() or require() (or the *_once versions) an absolute pathname, that file will be included. An absolute pathname starts with a ‘/’ on unix, and with a drive letter and colon on Windows.

If you give a relative path (any other path), PHP will search the directories in the configuration value ‘include_path’ in order, until a match is found or there are no more directories to search.

So, in short, to include an absolute filename, give an absolute filename. See also the function realpath().

If you want to set your own include ‘root’, have a look at this question (specifically my answer of course 🙂