selected checkbox in Controller!!!!

hi,
I have the following problem:

product.controller.rb

class Product Controller

def show
.....
end

end

show.rhtml.rb
.
.
    <% Product.find (: all). each do | product|
      <% = Check_box "product", "name",: checked => false,: onchange => "#
(remote_function (: url => (: controller => 'product',: action => 'show') ))
"%> <br>
<% End%>
how can i get all the selected checkboxes in the show-action(controller)?

Thnaks im advance