uploaddatabyxl

     <%= form_tag({action: 'storedata', controller: 'profileinfo'}, multipart: true) do %>
        <%= file_field_tag :file %>
        <%= submit_tag %>
     <% end %>

 <form accept-charset="UTF-8" action="/profileinfo/storedata" enctype="multipart/form-data" method="post">
      <div style="margin:0;padding:0;display:inline">
        <input name="utf8" type="hidden" value="&#x2713;" />
         <input name="authenticity_token" type="hidden" value="EMXCLkxw84pdO1+AWacyzti8ok8b5jDj5H6u2BmBBMc=" />
       </div>
            <input id="file" name="file" type="file" />
            <input name="commit" type="submit" value="Save changes" />
</form> 


http://stackoverflow.com/questions/11895829/uploading-file-in-rails-gives-string-filename-instead-of-file-or-stringio-object

http://guides.rubyonrails.org/v3.2.13/form_helpers.html#uploading-files

try putting multipart:true in brackets as well
<%= form_tag({action: 'storedata', controller: 'profileinfo'}, {multipart: true}) do %>