form_for, form_tag,multipart,polymorphic

form_for api
form_tag versus form_for with :multipart => true<br />#form_for url的部份可以這樣寫<br /><% form_for([@ad_buyer, @ad_file], :html => {:multipart => true}) do |f| %><br /> <%= f.error_messages %><br /> <%= f.submit "Create" %><br /><% end %><br /><% form_tag ({:action => 'upload_file'}, :multipart => true) do %><br /> <p><label for="upload_file">Select File</label> :<br /> <%= file_field 'upload', 'datafile' %></p><br /> <%= submit_tag "Upload" %><br /><% end %><br />