为什么file.original_filename在Ruby on Rails中不起作用？

Question

i am implementing a few weeks now in Ruby. And what i want to do is read in a csv file, which i put then in a temporary file so i can access it in next views and manipulate the data. I have implemented everything like examples on the internet, but i always get the error : undefined method `original_filename' for nil:NilClass

My code in my view is:

<% form_for :dump, :url=>{:controller=>"project_importer", :action=>"match"}, :html => { :multipart => true } do |f| -%>
<table">
   <tr>
     <td>
      <label for="dump_file">
        Select a CSV File :
      </label>
     </td>
     <td >
       <%= f.file_field :file -%>
     </td>
   </tr>

 </table>

and then in my controller i have:

file = params[:file]


   @original_filename = file.original_filename
    tmpfile = Tempfile.new("redmine_user_importer")
    if tmpfile
      tmpfile.write(file.read)
      tmpfile.close
      tmpfilename = File.basename(tmpfile.path)
      if !$tmpfiles
        $tmpfiles = Hash.new
      end
      $tmpfiles[tmpfilename] = tmpfile
    else
      flash[:error] = "Cannot save import file."
      return
    end

I really don't know what i am doing wrong, i hope someone can help me out. The file param is not empty.

Thanks in advance!

Answer 1

try

params[:dump][:file]

instead of

params[:file]

Or print

<%= params.inspect %>

on the target page to inspect your params if this doesnt work.