Using querystring variable in RewriteRule

[sxtrail]

Hi there

I was hoping someone could give me a solution to the following problem as I'm stuck....

I have a .htaccess file which I use to rewrite search engine friendly URLs into PHP URLs so that the script can use the $_GET values. It looks something like this:

RewriteEngine On
RewriteRule ^([a-zA-Z0-9-]+)-([0-9]+)-([0-9]+).html$      product_list.php?cid=$2&bid=$3 [L]

What I want to do is also be able to read querystring variables that may be appended to the search engine friendly URL. For example, the URL could be:

CategoryTitleHere-25-3.html?sort=4

So, I changed the .htaccess file to:

RewriteEngine On
RewriteCond %{QUERY_STRING} ^sort=([0-9])?$
RewriteRule ^([a-zA-Z0-9-]+)-([0-9]+)-([0-9]+).html$      product_list.php?cid=$2&bid=$3&sort=%1 [L]

This works. BUT, it doesn't work if the sort variable isn't present. How can I change the RewriteCond so that it doesn't matter if there isn't a querystring? Also, how can it be amended to include additional querystring variables such as 'page'? Basically, it needs to work with URLs like this:

CategoryTitleHere-25-3.html
CategoryTitleHere-25-3.html?sort=6
CategoryTitleHere-25-3.html?sort=6&page=2

Any help would be much appreciated

[Dan Grossman]

If you add the [QSA] flag on your original rule, it'll pass along any query string variables there in addition to the ones you created. mod_rewrite is smart like that, you won't need these additional rules or conditions.

[sxtrail]

Hi Sounds good. But how would I rewrite my existing rule so that it can read the querystring values for 'sort' and 'page', which may or may not be there?

Many thanks.

edit:
Does this look correct:

RewriteRule ^([a-zA-Z0-9-]+)-([0-9]+)-([0-9]+).html([\?sort=0-9]?)$          product_list.php?cid=$2&bid=$3&sort=$4 [QSA,L]

If so, would I just amend it as follows to include page?:

RewriteRule ^([a-zA-Z0-9-]+)-([0-9]+)-([0-9]+).html([\?sort=0-9]?)([page=0-9]?)$          product_list.php?cid=$2&bid=$3&sort=$4&page=$5 [QSA,L]

[Dan Grossman]

You do not include "sort" or "page" at all

Use your original rule, just add [QSA] flag

It will append any query string that is there

RewriteRule ^([a-zA-Z0-9-]+)-([0-9]+)-([0-9]+).html$      product_list.php?cid=$2&bid=$3 [QSA,L]

[sxtrail]

Ahhh, I see. That is superb, thanks I can't believe I didn't find such a solution when googling. In fact, some solutions I found seemed too complex with no mention of the QSA flag. Obviously I'm new to mod_rewrite, but I'm really starting to love it now. Thanks again!