AH.. I just looked at the link the OP provided. I think I misunderstood the OPs question. Those six methods are for developers to use in order to load content of another webpage.
I think OP wants to protect CONTENT, not the PHP files, themselves.
Is there a way around that? I don't think so. Basically, if content is viewable, it can be "screen-scraped" or even manually saved via browser for others to pilfer. The only safeguards would be to do things like watermark images so that they would be unusable on another site. But as far as text is concerned, it's pretty much available to any method of capture - all you can really do is put copyright symbols on it, and occasionally peruse the web to see if anyone else has the exact same content on their site. If you do find your (and I mean "it belongs to you") content, contacting the host provider usually resolves the issue. If not, then a letter from a lawyer threatening litigation usually will suffice. Beyond that, you have to actually sue to get your content off of another site that has pilfered it.