Python List Files

Introduction

Listing files in a directory is a common task in file management. Python provides several ways to list files in a directory, including the os module, the os.path module, and the glob module. Each method has its advantages and can be used depending on your specific needs.

Using the os Module

The os module provides a portable way of using operating system-dependent functionality, including listing files in a directory.

os.listdir()

The os.listdir() function returns a list containing the names of the entries in the directory given by path.

Example

import os

# List files in the current directory
files = os.listdir('.')
print(files)

Output

['file1.txt', 'file2.txt', 'directory1', 'script.py']

Filtering Files

You can filter the list to include only files and exclude directories.

import os

# List files in the current directory, excluding directories
files = [f for f in os.listdir('.') if os.path.isfile(os.path.join('.', f))]
print(files)

Output

['file1.txt', 'file2.txt', 'script.py']

Using os.walk()

The os.walk() function generates the file names in a directory tree by walking either top-down or bottom-up.

Example

import os

# List all files in a directory tree
for root, dirs, files in os.walk('.'):
    for file in files:
        print(os.path.join(root, file))

Output

./file1.txt
./file2.txt
./script.py
./directory1/file3.txt

Using the glob Module

The glob module finds all the pathnames matching a specified pattern according to the rules used by the Unix shell. It can be used to list files with specific patterns.

Example

import glob

# List all .txt files in the current directory
txt_files = glob.glob('*.txt')
print(txt_files)

Output

['file1.txt', 'file2.txt']

Recursive Listing

You can use the glob module to list files recursively by using the ** pattern.

import glob

# List all .txt files in the current directory and subdirectories
txt_files = glob.glob('**/*.txt', recursive=True)
print(txt_files)

Output

['file1.txt', 'file2.txt', 'directory1/file3.txt']

Using the pathlib Module

The pathlib module provides an object-oriented approach for working with filesystem paths. It offers an easy way to list files in a directory.

Example

from pathlib import Path

# List files in the current directory
files = [f for f in Path('.').iterdir() if f.is_file()]
print(files)

Output

[PosixPath('file1.txt'), PosixPath('file2.txt'), PosixPath('script.py')]

Filtering by Extension

You can filter files by their extension using the glob method from pathlib.

from pathlib import Path

# List all .txt files in the current directory
txt_files = list(Path('.').glob('*.txt'))
print(txt_files)

Output

[PosixPath('file1.txt'), PosixPath('file2.txt')]

Recursive Listing

You can list files recursively by using the rglob method.

from pathlib import Path

# List all .txt files in the current directory and subdirectories
txt_files = list(Path('.').rglob('*.txt'))
print(txt_files)

Output

[PosixPath('file1.txt'), PosixPath('file2.txt'), PosixPath('directory1/file3.txt')]

Conclusion

Listing files in Python can be done using various modules and methods. The os module provides basic functionality for listing files and directories, while the glob module offers pattern matching capabilities. The pathlib module provides an object-oriented approach for handling filesystem paths and can be used for both simple and recursive listings. Understanding these methods allows you to efficiently manage and process files in Python applications.