Ruby List File in Folder

1. Create a Sample Folder
2. Use Dir::[] to List All Files in a Folder
3. Use Dir.glob to List All Files in a Folder

This article will introduce different ways to list all files in a particular folder in Ruby.

Create a Sample Folder

Please use these command lines to create a folder structure in your current directory.

mkdir parent_folder
touch parent_folder/music_1.txt
touch parent_folder/music_2.txt

mkdir parent_folder/child_folder
touch parent_folder/child_folder/doc_1.txt
touch parent_folder/child_folder/doc_2.txt

Use Dir::[] to List All Files in a Folder

Use Dir[<path_to_folder>/*], it returns an array containing all file names and folder names inside path_to_folder.

Afterward, we’ll use the File.file? method to select the file names from the result.

Example:

files = Dir['parent_folder/*'].select { |path| File.file?(path) }
puts files

Output:

parent_folder/music_1.txt
parent_folder/music_2.txt

To list files recursively inside subfolder, we can apply this pattern:

files = Dir['parent_folder/**/*'].select { |path| File.file?(path) }
puts files

Output:

parent_folder/music_1.txt
parent_folder/music_2.txt
parent_folder/child_folder/doc_2.txt
parent_folder/child_folder/doc_1.txt

Use Dir.glob to List All Files in a Folder

Calling Dir.glob is equivalent to calling Dir[<path_to_folder>].

Example:

files = Dir.glob('parent_folder/**/*').select { |path| File.file?(path) }
puts files

Output:

parent_folder/music_1.txt
parent_folder/music_2.txt
parent_folder/child_folder/doc_2.txt
parent_folder/child_folder/doc_1.txt

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