Extract data from Links (like on Facebook), but extract filename.php links not html?

[Attila_phpfreak]

So I have been working on my website for a while which all is php&mysql based, now working on the social networking part building in similar functions like Facebook has. I encountered a difficulty with getting information back from a link. I've checked several sources how it is possible, with title 'Facebook Like URL data Extract Using jQuery PHP and Ajax' was the most popular answer, I get the scripts but all of these scripts work with html links only. My site all with php extensions and copy&paste my site links into these demos do not return anything . I checked the code and all of them using file_get_contents(), parsing through the html file so if i pass 'filename.php' it returns nothing supposing that php has not processed yet and the function gets the content of the php script with no data of course. So my question is that how it is possible to extract data from a link with php extension (on Facebook it works) or how to get php file executed for file_get_contents() to get back the html?

here is the link with code&demo iamusing: http://www.sanwebe.com/2013/06/extract-url-content-like-facebook-with-php-and-jquery

thanks in advance.