.htaccess RewriteRule apache: how to rewrite based on URL parameter?

Question

I have URLs with lots of parameters, here is an example that looks like this:

http://www.mysite.com/profile?reset=1&force=1&gid=9&custom%5F18=BS+Forestry%2C+University+of+Kentucky

I would like to do a RewriteRule that redirects any request containing the string:

&custom

To a static HTML page such as:

http://www.mysite.com/foo.html

Can someone tell me if/how this is possible?

Thanks a lot!

Answer 1

This should do the trick:

RewriteCond %{QUERY_STRING}  (^|&)custom(&|$)
RewriteRule ^(.*)$ http://www.mysite.com/foo.html [R]