IIS7 and rewriteMap for friendly URL's - iis-7

Question

I have an external "rewritemaps.config" file with the following entries:
<rewriteMaps>
<rewriteMap name="Cat1">
<add value="2" key="wheels-and-castors" />
<add value="3" key="agricultural" />
<add value="4" key="hydraulic-hose-and-fittings" />
<add value="5" key="engineering-plastics" />
<add value="6" key="sealing-and-jointing" />
<add value="7" key="health-and-safety" />
<add value="8" key="hose-and-ducting" />
<add value="9" key="hose-couplings-and-clamps" />
<add value="10" key="general-consumables" />
<add value="11" key="ceramics" />
<add value="12" key="rubber-and-polyurethane" />
</rewriteMap>
</rewriteMaps>
How do I rewrite URL's such as:
http://www.domain.com/wheels-and-castors/
to the following:
http://www.domain.com/category.asp?catID=2
Note, this is a rewrite, and not a redirect.
I think I'm almost there with the final rewrite line, but I'm struggling on the match and conditions. My current final rewrite line is:
<action type="Rewrite" url="category.asp?catID={Cat1:{C:1}}" appendQueryString="false" />
(where Cat1 is the name of my rewriteMap)
Thanks for any help. Cheers, Chris.

Answer 1

Ok, after a good week of researching and trial & error, I've got it working. Here's the complete rule I'm using, which references an external "rewritemaps.config".
<rule name="Match Category URLs" stopProcessing="true">
<match url="^(?![^/]+?\.(?:css|png|jpg|axd)$)([^/]+)/?$" />
<conditions>
<add input="{URL}" pattern="(.asp|.xml)" negate="true" />
</conditions>
<action type="Rewrite" url="category.asp?catID={CatMap:{R:1}}" appendQueryString="false" />
</rule>
Works perfectly now.
PS. I renamed the rewriteMap to "CatMap" (to avoid anyone getting confused, if following this).