CODEWITHSUNDEEP
pythonpython-3.xfor-loop
user5012239
user5012239

Reputation:

Put names of .txt files into a list

This is my code, pinched from this site:

import os
for file in os.listdir("C:\\"):
    if file.endswith(".txt"):
        file = file.strip(".txt")
        print(file)

It works great, but I want to be able to manipulate my results and store them into a list, and I'm not sure how to do that. It's probably super simple and missing me completely, I'm sort of a noob. Thanks :)

EDIT:

I removed the readlines part, that wasn't meant to be there. What I am trying to do is get the names of every .txt file in the folder, in this case the folder is C:\

Upvotes: 1

Views: 106

Answers (2)

ShadowRanger
ShadowRanger

Reputation: 155734

A couple alternatives to incBrain's (perfectly fine) answer.

First, to simplify your own code instead of reinventing the wheel, use glob.glob:

import glob

onlytxt = [file[:-4] for file in glob.glob('C:\\*.txt')]

Or to get higher performance on Python 3.5+ (or any version of Python using the scandir module from PyPI):

import os  # Pre-3.5, you'd import and use the scandir module from PyPI

# Use file.path[:-4] to store the full path (sans .txt extension)
# where file.name[:-4] only gets the file name without the path or extension
onlytxt = [file.name[:-4] for file in os.scandir('C:\\') if file.name.endswith('.txt')]

Or for true ridiculousness, push more work to the C layer and avoid redundancy by splitting off the extension once, instead of one check for it, then another operation to strip it:

import os
from operator import attrgetter

components = map(os.path.splitext, map(attrgetter('name'), os.scandir('C:\\')))
onlytxt = [root for root, ext in components if ext == 'txt']

os.scandir doesn't do much for you in this case (you're not reading any attributes it might have checked for you), but in a largish directory, it means you aren't storing all entries at once (os.listdir and most other APIs read the complete contents of the directory into a list first before you have a chance to filter it), so peak memory usage is reduced when few files are matched.

Upvotes: 2

Dimitri Podborski
Dimitri Podborski

Reputation: 3784

Probably you want to have something like this:

import os
allfiles = os.listdir('C:\\')
onlytxt = [x for x in allfiles if x.endswith('.txt')]
print onlytxt

if you don't want to have .txt in the list do this:

onlytxt = [x[:-4] for x in allfiles if x.endswith('.txt')]

Upvotes: 1

Related Questions