Try File.basename
Returns the last component of the filename given in file_name, which must be formed using forward slashes (“/’’) regardless of the separator used on the local file system. If suffix is given and present at the end of file_name, it is removed.
File.basename("/home/gumby/work/ruby.rb") #=> "ruby.rb" File.basename("/home/gumby/work/ruby.rb", ".rb") #=> "ruby"
In your case:
File.basename("C:\\projects\\blah.dll", ".dll") #=> "blah"