Python file access by user input

Question

Here is a function in my code, I have a previously written file called numbers.txt . I am trying to read that file should they enter numbers or numbers.txt. However, it prints the file no matter what input is entered.

userfile = input('Please enter file name: ')
if userfile == 'numbers' or 'numbers.txt':
    f = open('numbers.txt','r')
    for line in f:
       print(line)
else:
    print('Sorry, this file does not exist')

`if userfile=='numbers' or userfile=='numbers.txt':` – Rakesh May 02 '18 at 12:27 — Rakesh, May 02 '18 at 12:27
Or `if userfile in ('numbers', 'numbers.txt'):` – glibdud May 02 '18 at 12:27 — glibdud, May 02 '18 at 12:27
try `if userfile=='numbers' or userfile=='numbers.txt':` – SShah May 02 '18 at 12:28 — SShah, May 02 '18 at 12:28

score 0 · Accepted Answer · answered May 02 '18 at 12:29

0

The problem is this line:

if userfile=='numbers' or 'numbers.txt':  # After the or

In python a string is True if it's not empty ('') so 'numbers.txt' is True. Change it to :

if userfile == 'numbers' or userfile == 'numbers.txt':

answered May 02 '18 at 12:29

Yassine Faris

951
6
26

score 0 · Answer 2 · answered May 02 '18 at 12:30

userfile=input('Please enter file name: ')
if (userfile=='numbers') or (userfile=='numbers.txt'):
    try:
        f=open('numbers.txt','r')
    except:
        print('Sorry, this file does not exist')
        exit()
    for line in f:
       print(line)
else:
    print('Sorry, this file does not exist')

Python file access by user input

2 Answers2