Need PHP or Regex script for matching URL's

Question

I'm changing all the URL's on my websites to lower case. I'm also replacing all the underscores with dashes. So the URL /World/New_York would become /world/new-york.

However, I don't want to lose traffic from links that are still pointing to /World/New_York, so I'd like that link to work as well. As I understand it, I can use an Apache file to automatically change the URL's in the browser to the correct format (lower case).

So what I want to do right now is simply make sure that all relevant links are accepted, 1) regardless of case and 2) regardless of whether words are separated by _, - or a simple space...

/world/new-york /World/New-York /WORLD/New York /wORld/new_YORK

All of the above URL's should be accepted, because 1) they all have the same characters, and 2) the words are separated by a dash, underscore or space.

In my PHP code, the URL is represented by the value $MyURL. So if you visit MySite/world/new-york, $MyURL = new-york, where new-york is a MySQL database value.

So I think what I need to do is create a script that says $MyURL = 1) the database value, or 2) the database value with an allowance for alternate case values, and/or 3) the database value with the dash replaced by an underscore or space. I would then insert this script before my page display query (below).

Can anyone tell me how to write such a script using either PHP or regular expression?

$sql= "SELECT COUNT(URL) AS num FROM orgs
WHERE URL = :MyURL";
$stmt = $pdo->prepare($sql);
$stmt->bindParam(':MyURL',$MyURL,PDO::PARAM_STR);
$stmt->execute();
$Total = $stmt->fetch();

---

@ Shahar...

Below is some code from one of my .htaccess files, where I inserted your code...

RewriteEngine On
RewriteRule ^test\.htm$ test.php [L]
Options -MultiViews

#Your suggested rule...
RewriteRule ^/(.*)$ /${lower:$1}

php_flag magic_quotes_gpc Off

RewriteRule ^topics/([a-zA-Z0-9()_/-]+)/?$ topics/index.php?topic=$1 [L]
RewriteRule ^world/([a-zA-Z0-9()_/-]+)/?$ world/index.php?area=$1 [L]

But when I type in px/Topics/Ethics, I get a NOT FOUND error. When I change it to px/topics/Ethics or px/topics/ethics it works. However, I'd like Ethics to change to ethics.

One of my concerns is statistics. I don't want to check my daily statistics and see 16 hits for Topics/Ethics, 13 for topics/Ethics and 3 for topics/ethics. Rather, I'd like to see 32 hits for topics/ethics. Apache is way over my head, though. ;)

Answer 1

If you want to convert the URL's to lowercase automatically, use mod_rewrite . This is what you need to add:

RewriteMap lower int:tolower
RewriteRule  ^([^/]+)/?$  yourdir/${lower:$1}

You didn't specify what yourdir was... Or just do: RewriteRule ^/(.*)$ /${lower:$1} .

Using PHP, you can just do strtolower() . Although, I don't quite understand why. I believe MySQL searches are case-insensative.

EDIT: Also, for the replacing part, I think this should work:

RewriteRule ^(.*)\_(.*)$ $1\-$2
RewriteRule ^(.*)\%20(.*)$ $1\-$2

The first will replace _ with - , the second will replace space ( $20 ) with - .