Remove File Extension and URL Variable using .htaccess - php

Question

I'm making up myself a small blog and I found a useful .htaccess file to remove file extensions:
AddType text/x-component .htc
RewriteEngine On
RewriteBase /
# remove .php; use THE_REQUEST to prevent infinite loops
RewriteCond %{THE_REQUEST} ^GET\ (.*)\.php\ HTTP
RewriteRule (.*)\.php$ $1 [R=301]
# remove index
RewriteRule (.*)/index$ $1/ [R=301]
# remove slash if not directory
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} /$
RewriteRule (.*)/ $1 [R=301]
# add .php to access file, but don't redirect
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteCond %{REQUEST_URI} !/$
RewriteRule (.*) $1\.php
This works just fine and all pages are showing up .php less. I know wanted to extend this so when I click a link to a specific blog post (say /blog/index.php?art=1) it just shows in the url as website/blog/1. I thought to tag on to the end of the .htaccess file:
RewriteRule ^blog/(.*)$ blog/index.php?art=$0 [L]
But that doesn't seem to be working. EDIT Actually it breaks the blog page so no snippets are pulled through from the DB
My .htaccess file is in the root directory and the blog files are /root/blog/index.php
Any help would be gratefully appreciated

Answer 1

Unlike most other languages, the parameters in .htaccess are not 0-based. To access the first parameter, you should use $1, not $0.
The following should work:
RewriteRule ^blog/(.*)$ blog/index.php?art=$1 [L]
It might also be worthwhile to add some tests in there, for example you might only want numerical values passed to art, so you can improve it using:
RewriteRule ^blog/([0-9]+)$ blog/index.php?art=$1 [L]
Also, it might be worthwhile to add the QSA flag, since this will also preserve any query string that is passed in the original URL:
RewriteRule ^blog/([0-9]+)$ blog/index.php?art=$1 [L,QSA]