Rails 3: Upload csv file with non-english characters

I've a CSV file. If the file contains only english characters everything works fine, file uploads and contains data. But, if the file contains non-english characters, it's uploads but uploaded file is empty.

Hope, anybody can help.

UPDATE:

Background: Rails: rails 3.0.9, Ruby: ruby 1.9.2

Form:

<%= form_tag({:action => :import}, :multipart => true) do |f| %>
  <%= collection_select(:contact, :list_id, current_user.lists, :id, :title) %>
  <%= file_field_tag 'upload' %>
  <%= submit_tag("Import") %>
<% end %>

Controller:

def import
  begin
    Contact.upload(params[:upload], current_user, params[:contact][:list_id])
    redirect_to :action => "index"
  rescue Exception => e
  end
end

Model:

def upload(uploaded_io, user_id, list_id)
  File.open(Rails.root.join('public', 'up开发者_JS百科loads', uploaded_io.original_filename), 'w') do |file|
    file.write(uploaded_io.read)
  end

  self.import(uploaded_io.original_filename, user_id, list_id)
end

check this library, it deals with different encodings: Iconv

I think you should use it in your upload method (with IO operations)

I've resolve a problem. It starts working as expected then I've change 'w' to 'wb' for opening file in a binary mode.

Thank you! Hope its help someone else.