How do you get a directory listing sorted by their name in Python?

When working with directories in Python, it's often necessary to obtain a list of files and subdirectories within a given directory. Moreover, sorting this directory listing by their names can be beneficial for better organization and readability. Python provides several methods and techniques to achieve this goal efficiently. Sorting the directory listing alphabetically can help you quickly locate specific files or directories and facilitate various file management tasks.

In this comprehensive article, we will explore different methods to get a directory listing sorted by name in Python. We will provide step−by−step explanations and code examples to guide you through the process. Whether you prefer using the "os" module, the "pathlib" module, or custom sorting functions, this guide will equip you with the tools to navigate and organize directory contents effectively.

Let's embark on this journey of directory exploration with Python and discover the secrets of obtaining sorted directory listings!

Using os.listdir() with Sorted()

The "os.listdir()" function allows us to obtain a list of items (files and directories) within a given directory. By using the "sorted()" function, we can sort this list alphabetically.

Example

• In the code below, we import the "os" module, which provides functions for interacting with the operating system, including directory operations.

• The "sorted_directory_listing_with_os_listdir()" function takes the "directory" as input and returns the directory listing sorted by name using "os.listdir()" and "sorted()".

• We use "os.listdir(directory)" to obtain a list of items (files and directories) in the specified directory.

• The "sorted()" function then sorts the list alphabetically, and the sorted list is returned.

import os

def sorted_directory_listing_with_os_listdir(directory):
    items = os.listdir(directory)
    sorted_items = sorted(items)
    return sorted_items

Utilizing os.scandir() with Sorted()

The "os.scandir()" function is a more efficient alternative to "os.listdir()" for getting directory contents. We can use "sorted()" with a custom key function to achieve the desired alphabetical sorting.

Example

• In this example, we use the "os.scandir()" function along with "sorted()" to obtain a sorted directory listing in Python.

• The "sorted_directory_listing_with_os_scandir()" function takes the "directory" as input and returns the sorted directory listing using "os.scandir()" and "sorted()".

• The "with" statement is used to ensure proper resource cleanup after the block's execution.

• We use a lambda function as the "key" argument in "sorted()", which specifies that the sorting should be based on the "name" attribute of each entry returned by "os.scandir()".

• The sorted directory entries are then converted into a list of names, and the sorted list is returned.

import os

def sorted_directory_listing_with_os_scandir(directory):
    with os.scandir(directory) as entries:
        sorted_entries = sorted(entries, key=lambda entry: entry.name)
        sorted_items = [entry.name for entry in sorted_entries]
    return sorted_items

Using pathlib.Path.glob() with Sorted()

The "pathlib" module provides a more modern and convenient way to handle file paths. We can use "sorted()" with "Path.glob()" to get a sorted directory listing.

Example

• In this example, we import the "Path" class from the "pathlib" module, which represents a file system path.

• The "sorted_directory_listing_with_pathlib_glob()" function takes the "directory" as input and returns the sorted directory listing using "Path.glob()" and "sorted()".

• We create a "Path" object with "Path(directory)", where "directory" is the input directory.

• We use "path_object.glob('*')" to obtain an iterator of items (files and directories) in the specified directory.

• The lambda function in "sorted()" specifies that the sorting should be based on the "name" attribute of each item returned by "path_object.glob()".

• The sorted items are then converted into a list of names, and the sorted list is returned.

from pathlib import Path

def sorted_directory_listing_with_pathlib_glob(directory):
    path_object = Path(directory)
    items = path_object.glob('*')
    sorted_items = sorted(items, key=lambda item: item.name)
    return [item.name for item in sorted_items]

Custom Sorting with sorted() and key Function

In some cases, you may need to sort the directory listing based on criteria other than the default alphabetical order. You can use a custom key function with "sorted()" to achieve this.

Example

• The "custom_sorted_directory_listing()" function demonstrates how to use "sorted()" with a custom key function for directory listing sorting.

• The function takes the "directory" as input and returns the directory listing sorted based on custom criteria using "sorted()" with a custom key function.

• We define the "sort_criteria()" function within "custom_sorted_directory_listing()". This function takes an "item" (file or directory name) and returns the size of the item (in bytes) using "os.path.getsize()".

• We use "os.listdir(directory)" to obtain a list of items (files and directories) in the specified directory.

• The "sorted()" function then sorts the list of items based on the values returned by the " sort_criteria()" function.

• The sorted list is returned.

import os

def custom_sorted_directory_listing(directory):
    def sort_criteria(item):
        return os.path.getsize(os.path.join(directory, item))
    
    items = os.listdir(directory)
    sorted_items = sorted(items, key=sort_criteria)
    return sorted_items

Sorting in Reverse Order

You can also sort the directory listing in reverse order (descending) by setting the "reverse" parameter of "sorted()" to "True".

Example

• The "reverse_sorted_directory_listing()" function illustrates how to sort the directory listing in reverse order using "sorted()" with the "reverse" parameter.

• The function takes the "directory" as input and returns the directory listing sorted in reverse order using "sorted()" with "reverse=True".

• We use "os.listdir(directory)" to obtain a list of items (files and directories) in the specified directory.

• The "sorted()" function sorts the list in reverse order, and the sorted list is returned.

import os

def reverse_sorted_directory_listing(directory):
    items = os.listdir(directory)
    reverse_sorted_items = sorted(items, reverse=True)
    return reverse_sorted_items

In this comprehensive guide, we've explored various methods to get a directory listing sorted by name in Python. Whether you prefer using the "os" module or the "pathlib" module, Python provides multiple options to efficiently obtain and organize directory contents. Additionally, we've learned how to apply custom sorting criteria and sort the listing in reverse order. By mastering these techniques, you can easily manage and navigate directory structures, making your file handling tasks more efficient and organized.