How to count the length (number of lines) of a csv file in Rails?
- by Mathias
Hello,
I have a form (Rails) which allows me to load a .csv file using the file_field.
In the view:
<% form_for(:upcsv, :html => {:multipart => true}) do |f| %>
<table>
<tr>
<td><%= f.label("File:") %></td>
<td><%= f.file_field(:filename) %></td>
</tr>
</table>
<%= f.submit("Submit") %>
<% end %>
Clicking Submit redirects me to another page (create.html.erb). The file was loaded fine, and I was able to read the contents just fine in this second page. I am trying to show the number of lines in the .csv file in this second page.
My controller (semi-pseudocode):
class UpcsvController < ApplicationController
def index
end
def create
file = params[:upcsv][:filename]
...
#params[:upcsv][:file_length] = file.length # Show number of lines in the file
#params[:upcsv][:file_length] = file.size
...
end
end
Both file.length and file.size returns '91' when my file only contains 7 lines. From the Rails documentation that I read, once the Submit button is clicked, Rails creates a temp file of the uploaded file, and the params[:upcsv][:filename] contains the contents of the temp/uploaded file and not the path to the file. And I don't know how to extract the number of lines in my original file. What is the correct way to get the number of lines in the file?
My create.html.erb:
<table>
<tr>
<td>File length:</td>
<td><%= params[:upcsv][:file_length] %></td>
</tr>
</table>
I'm really new at Rails (just started last week), so please bear with my stupid questions.
Thank you!
