hidden_field_tag and hidden_field

<%= hidden_field_tag :version,@version %>
<%= hidden_field_tag :module_id,@video.parent_module_id%>

here is the log file

{"utf8"=>"✓", "authenticity_token"=>"fixQgc0R4wHIn6fbE+Kkf+JC7oQP/WuNBBCDID6Q5Fw=", "version"=>"1", "module_id"=>"1", "video"=>{"video_id"=>"", "show_id"=>"", "title"=>"", "res_desc"=>"", "large_horizontal_image"=>"", "middle_horizontal_image"=>"", "large_vertical_image"=>"", "middle_vertical_image"=>""}, "commit"=>"保存"}

==========================================

<%= v.hidden_field :version %>
<%= v.hidden_field :parent_module_id %>

Parameters: {"utf8"=>"✓", "authenticity_token"=>"fixQgc0R4wHIn6fbE+Kkf+JC7oQP/WuNBBCDID6Q5Fw=", "video"=>{"version"=>"1", "parent_module_id"=>"1", "video_id"=>"qq", "show_id"=>"qq", "title"=>"q", "res_desc"=>"qq", "large_horizontal_image"=>"", "middle_horizontal_image"=>"", "large_vertical_image"=>"", "middle_vertical_image"=>""}, "commit"=>"保存"}