Add a character set to Vpim's Vcard-Export

If you are using Vpim to export Vcards and ever need to include a character set on your lines in the generated Vcard-file, here's how to do it:

# open up Vpim's DirectoryInfo::Field class
module Vpim
  class DirectoryInfo
    class Field
      class << self
        alias_method :orig_create, :create
        
        # we overwrite Field.create for setting the CHARSET
        def create(name, value='', params={})
          # specify the lines you don't want to add a charset to
          lines_to_ignore = %w(BEGIN END VERSION)
          params.merge!({'CHARSET' => 'ISO-8859-1'}) unless lines_to_ignore.include? name
          orig_create(name, value, params)
        end
      end
        
    end
  end
end