How to have a PHP file be used for multiple URLs - php

Question

I want to have a single PHP file that takes care of multiple URLs in a subdirectory.
For example, my site is http://www.startingtofeelit.com/. I want one php file, say, called playlist.php which would handle when a user goes to http://www.startingtofeelit.com/playlist/101 or if they go to http://www.startingtofeelit.com/playlist/142 etc. I want to be able to strip the number (101, 142 in my example urls above) to use as a variable (the playlist ID), so I can display the correct playlist.
I know that I can create an index.php in my playlist subdirectory and use GET variables like http://www.startingtofeelit.com/playlist?id=102 and get the ID that way, but this is much sloppier looking and I'd like to be able to know how to do it the other way.
My site is built on WordPress, but I don't think this should make a difference in any way.

Answer 1

Well, you cannot achieve this with PHP alone.
If you use Apache, you can use .htaccess
If you use IIS, you can use URL Rewrite
The basic idea behind those modules is to mapping from one URL to another URL. For example: you would want to map from
http://www.startingtofeelit.com/playlist/142 =>
http://www.startingtofeelit.com/playlist.php?id=142
You can express the URL mapping in regular expression. For example, in .htaccess (Apache). You can write like this
RewriteRule ^playlist/([0-9]+)/?$ playlist.php?id=$1
Noted that, you need to have .htaccess file in your website directory. Since, you are using Wordpress, chance that you have existed .htaccess is high. You can simply append that line of code to existed .htaccess
The following is an explanation of the regular expression:
^playlist/ # any URL start with playlist/
([0+9]+) # following by number, and store it as $1
/?$ # end with or without /
Mapping to
playlist.php?id=$1 # where $1 is taken from the matched number from our pattern.

Answer 2

This is usually handled in a way similar to what you already tried. However, it's common to use a re-writing script so that your application will accept a clean URL such as:
http://www.startingtofeelit.com/playlist/142
...and re-write it for your application as such:
http://www.startingtofeelit.com/playlist?id=142
For example, if you're using an Apache web server and have the mod_rewrite module installed and enabled, you can use the following snippet in an .htaccess file and use your GET parameter as you indicated you already know how to do. Other popular web servers have unique URL re-writing modules that will let you do the same.
<IfModule mod_rewrite.c>
RewriteEngine On
# Rewrite this:
# http://www.example.com/somepage/1
# ...into this:
# http://www.example.com/somepage?id=1
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?/$1 [L]
</IfModule>