It's possible, but your going to have to install PHP on your localhost.

If this is on a Windows PC you could install WAMP, Install PHP 5 Apache MySQL on Windows : WampServer
On a Mac MAMP, MAMP: Mac, Apache, MySQL, PHP

I've been using WAMP on my local computer for about 2 years now and it's been very useful for me. It allows me to view an editted site offline before uploading on the web

[DELETED]

If its windows you can install quickphp which is a very small, easy to install lightweight php web server.

You can edit PHP files before uploading to a web server, just do it with Notepad or your favorite text editor. But if you want to see the results of a PHP file the way it looks on your website, you have to remember that PHP is mostly processed by the web server before it displays to the visitor's web browser. That's why you have load your own PHP web server on your laptop or desktop, if you want to see what a PHP file looks like without uploading. Be aware that you will need the same "stuff" on your local server that you have on the official web server. "Stuff" like PHP includes, images, Javascript .js files, and possibly the same version of PHP, if you want to duplicate a similar result for offline testing.

I think the recommendations given earlier are excellent choices. Let us know if you run into any problems or errors. Thanks!

download and install free software's WAMPserver run the software, keep your php files in www folder, type in your browser address bar
localhost and hit enter
you can see your files output in browser

Yes, if your OS is Windows you should have a Apache, PHP and MySQL. If your those three, put your PHP files in htdocs folder. If your site has database your MySQL should it open in command prompt, it not you can browser your PHP file in your browser in you PC.