sanitizing strings

Hey guys this should be an easy one,
how do i define a method that i can reuse for strings.

eg/ "mystring".sanitize

i know how to write the regex for such a method but where would i put it ???

cheers Adam

i think i may have answered it ......

   String.class_eval do
     # define new method
     def sanitize
       self.gsub(/[^[:alnum:]]+/, '_')
     end
   end

i dumed that into my app controller and its working

class String
def sanitize
self.gsub(/[^[:alnum:]]+/, ‘_’)
end
end
end

Is better looking

Thanks.

Where is the ideal place to put that??

I have a file in my lib called custom_methods.rb, I load it by doing require ‘custom_methods’ in my environment file, I put all my class additions in there.