如何从多个子文件夹中随机选择 select 文件

Question

I've multiple sub-folders and each sub-folder has multiple files. I need to select the sub-folder randomly and then need to select a random file in that sub-folder. Let's say I've five folders A, B, C, D, E, and each folder contains another folder named data and this data folder contains multiple files. I need to pick the folder randomly from the five folders and then open the data folder and finally randomly select a file.

Answer 1

Keep the folder names in a list. import random import os folders = [0,1,2,3,4] selected_folder = random.choice(folders) path = selected_folder+"/data"

Now to take random file from the path, do random.choice() and pass the list of files in that path. Use os.listdir(path) to get the list of files.

Answer 2

import os
import random

path = os.getcwd()

def getRandomFile(path):
    randomDir = random.choice([(x) for x in list(os.scandir(path)) if x.is_dir()]).name
    randomFile = random.choice([f for f in list(os.scandir(randomDir + "\\data\\"))]).name
    return randomFile

print(getRandomFile(path))

Answer 3

Try this: (Python file must be in the same main folder as those 5 folders)

import os,random
lst=list(filter(lambda x: os.path.isdir(x), os.listdir('.'))) //get folder list
folder=random.choice(lst) //select random folder
os.chdir(os.path.join(os.path.dirname(__file__), folder, 'data')) // goto random folder/data
lst=list(filter(lambda x: os.path.isfile(x), os.listdir('.'))) //get file list
file=random.choice(lst) //get random file
print(file)

Answer 4

As I understand, you actually need 4 functions to build your block of code:

• os.listdir(path) which list all files and directories at a location
• os.path.isdir(path) to check if a element in a location is a directory
• os.path.isfile(path) idem with a files
• random.randrange(X) to find a random number in the range [0; X[

I'm sure you can find easily the doc concerning those functions as they are all in the standard library of python. Anyway here is your code:

import os
import random

path = "/home/johndoe/"
dirs  = list(filter(lambda dir: os.path.isdir(os.path.join(path, dir)), os.listdir(path)))

dir_chosen = dirs[random.randrange(len(dirs))]

files_path = os.path.join(path, dir_chosen, "data")
files = list(filter(lambda file: os.path.isfile(os.path.join(files_path, file)), os.listdir(files_path)))

file_chosen = files[random.randrange(len(files))]

print("the file randomly chosen is: {}".format(os.path.join(files_path, file_chose )))

You can also check about os.path.join(a, b) if you don't know about it but it is basically equivalent to a + '/' + b on UNIX and a + '\' + b on Windows.