How can I make a stack-overflow style user URL? - .htaccess

Question

I'd like to map:
mywebsite.com/users/ -> mywebsite.com/users/users.php
mywebsite.com/users -> mywebsite.com/users/users.php
mywebsite.com/users/username -> mywebsite.com/users/user.php?name=username
At present, I'm using this .htaccess in the users directory:
RewriteEngine On
RewriteRule ^([a-zA-Z0-9_])*$ user.php?name=$1 [L]
RewriteRule ^.*$ users.php [L]
However, it never generates the user.php?name=$1 URL.
Why doesn't it work?

Answer 1

Here are the rules (place in .htaccess in website root folder. If placed elsewhere some tweaking is required):
Options +FollowSymLinks -MultiViews
RewriteEngine On
RewriteBase /
# 1
RewriteRule ^users/?$ /users/users.php [L]
# 2
RewriteCond %{REQUEST_URI} !^/users/users?\.php
RewriteRule ^users/([^/]+)$ /users/user.php?name=$1 [QSA,L]
Rule #1 will match fist 2 URLs of yours.
Rule #2 will work with specific user mapping. It will ensure that it does not rewrite already rewritten URLs.
UPDATE:
If you want to place it into .htaccess file in /users/ folder, then this URL mywebsite.com/users (without trailing slash) most likely will not work.
But in any case -- here are the rules:
Options +FollowSymLinks -MultiViews
RewriteEngine On
# 1
RewriteRule ^$ users.php [L]
# 2
RewriteCond %{REQUEST_URI} !^/users/users?\.php
RewriteRule ^([^/]+)$ user.php?name=$1 [QSA,L]

Answer 2

It looks to me like it is applying both rules in sequence: the url matches the first rule, so it adds user.php?name=$1, and then it matches the second rule, so it replaces the string with users.php. If that is the problem, then for your particular case you could fix it by replacing the second regular expression with ^/?$.