How write csv file without new line character in last line?

Question

I have a code like this to write csv file in python

import csv
with open('eggs.csv', 'wb') as csvfile:
    spamwriter = csv.writer(csvfile, delimiter=' ',
                            quotechar='|', quoting=csv.QUOTE_MINIMAL)
    spamwriter.writerow(['Spam'] * 5 + ['Baked Beans'])
    spamwriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])

output shown in in image. Now there is an extra line in output (line 3). How can i remove this last empty line while writing csv file.

Answer 1

Use file.seek to move file pointer before the last \r\n, then use file.truncate.

import os
import csv

with open('eggs.csv', 'wb') as csvfile:
    spamwriter = csv.writer(csvfile, delimiter=' ',
                            quotechar='|', quoting=csv.QUOTE_MINIMAL)
    spamwriter.writerow(['Spam'] * 5 + ['Baked Beans'])
    spamwriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
    csvfile.seek(-2, os.SEEK_END) # <---- 2 : len('\r\n')
    csvfile.truncate()            # <----

NOTE: You should change -2 if you use different lineterminator. I used -2 because \r\n is default lineterminator.

Answer 2

here is a solution that removes the newline symbols from last line of csv, using rstrip:

def remove_last_line_from_csv(filename):
    with open(filename) as myFile:
        lines = myFile.readlines()
        last_line = lines[len(lines)-1]
        lines[len(lines)-1] = last_line.rstrip()
    with open(filename, 'w') as myFile:    
        myFile.writelines(lines)