multiple checkboxes

form.rb

  serialize :product_categories  

<%= select_product_categories(@vendor.registration_request.product_categories) %>


  def select_product_categories(array)
    if array == nil or array.length == 0
      array = []
    end
    html = ""
    for pc in PRODUCT_CATEGORIES_JP
      html << "<div class='fixed_cell'>#{check_box_tag 'vendor[registration_request_attributes][product_categories][]', pc, array.include?(pc)}&nbsp;#{pc}</div>"        
    end
    return raw html
  end