How to add a page to header that is outside of WordPress?

Question

I have a page on my site that is not a page in WordPress. How can I add it to the header?

EDIT: The page is .php. It is outside of the theme structure.

Answer 1

The code you want is:

<?php include 'yourfile.php' ?>

Place the file in the same directory as header.php.

EDIT: depending on the nature of the content, and how often you will reuse, you may also choose to use this:

http://codex.wordpress.org/Function_Reference/get_template_part

Answer 2

You can simply add a template header comment and add your site as Page Template.

Just add the following line on top of your file:

<?php
/**
 * Template Name: My lovely standalone page
 */

Then add another page and choose your new template from the dropdown/select on the meta box on the right. You don't have to add any content or anything (I'd add a title in case it gets used) and your site will be integrated straight into WordPress. You then can even add it to menus, etc.