Can I use a wordpress theme in new php pages?

Question

I'm putting together a web site that needed to include some signup and blogging capability. Wordpress seems to be a perfect fit for that portion of the app, so I've started experimenting with it. I see plenty of tutorials on creating custom themes so I don't expect that to be a problem.

What I'm not able to figure out is what to do with the rest of my site. I will have other non-blogging related php pages that will access a database, etc. I see that wordpress has a capability for generic pages of static content, but these would need to be coded PHP pages. I just can't find a way of having the wordpress theme apply to other php pages outside of wordpress. I was hoping of just doing something like

wp_header();
blah blah
wp_sidebar();
blah blah
wp_footer();

but I'm not really seeing any examples or documentation on how this might be done. Am I missing a key piece of documentation?

EDIT: The answer is to essentially copy and paste a file from the theme, with one crucial addition:

require( dirname(__FILE__) . 'path_to_wp_root/wp-load.php');

That sets up the wordpress environment and allows me to call get_header(), get_sidebar(), get_footer(), etc.

Answer 1

What you should do is develop your other non-blogging related php pages as a wordpress plugin. There are plenty of references online on how to do this, for example:
http://www.tutorialized.com/view/tutorial/Creating-a-Custom-Wordpress-Plugin-from-Scratch/41834

Answer 2

Generally, "yes".

A well-designed WordPress theme uses mostly CSS/Stylesheets for display, and you are correct in your assumptions: Look through the "Codex" about Theme Design / Template Design (http://codex.wordpress.org/Stepping_Into_Templates).

Essentially you could base your design on some of the current theme files, but leave out "the loop".

Answer 3

I think what you really want to do is include wp-load.php at the top of your php file. This will give you access to all the wordpress functions (wp-header(), wp-footer(), etc).

Answer 4

Another option is to use Wordpress as the CMS for all content on your site. This is increasingly becoming popular, as Wordpress is quite good at non-blog-things these days.