File / folder path manipulation in Python

File / folder path manipulation in Python

Since the version of the main environment is 2.7, the information may be different after ver3.0. Please pardon.

<Os.path.exists> Check the existence of folders and files

Whether the folder exists

import os
folderpath = ("C:\\test_folder\\test1")
print(os.path.exists(folderpath))
# True

You can check if the specified folder exists by using os.path.exists. The result is returned as bool.

** Be careful of the escape sequence \ when specifying the folder path. ** ** Add r and write r" C: \ Users \ xxx \ desktop \ xxx " or Alternatively, you can use \\ to recognize \ as a character string and write " C: \\ Users \\ xxx \\ desktop \\ xxx ".

Whether the file exists

import os
filepath = ("C:\\test_folder\\test1\\sample.txt") 
print(os.path.exists(filepath))
# True

If you specify the file name directly, you can check the existence of the file.

<Os.path.isfile> Judge that the file exists

import os
filepath = ("C:\\test_folder\\test1\\sample") 
print(os.path.isfile(filepath))

# True

True is returned if the specified file exists. If it is a folder or the file does not exist, False is returned.

Judge that the <os.path.isdir> folder exists

import os
filepath = ("C:\\test_folder\\test1") 
print(os.path.isdir(filepath))

# True

True is returned if the specified folder exists. If it is a file, or if it does not exist, False is returned.

Examine the details of the files in the <os.listdir> folder

import os
folderpath = ("C:\\test_folder\\test1")
print(os.listdir(folderpath))

#['test2''test1.bmp','test1.txt']

The files and folders that exist in the specified folder are stored in the list. The data in the subfolders will not be displayed.

<Os.walk> Check the contents of the subfolder

import os

filepath = ("C:\\test_folder\\test1")  
for i in os.walk(filepath):
    print(i)

#('C:\\test_folder\\test1', ['test2'], ['test1-A.txt', 'test1-B.txt'])
#('C:\\test_folder\\test1\\test2', [], ['test2-A.txt', 'test2-B.txt'])

A tuple is created. It consists of three elements (folder path, subfolder name, file name). The output information is appropriate.

Example) Extract only the file name

import os

filepath = ("C:\\test_folder")  
for folder,subfolder,filename in os.walk(filepath):
    print(filename)

#['test1-A.txt', 'test1-B.txt']
#['test2-A.txt', 'test2-B.txt']

The for statement is turned with the three elements of folder, subfolder, and filename, and only the filename is printed. It is necessary to process the data when actually using it.

Summary

There seems to be no big difference between 2.7 and 3.0.

Referenced page

https://tonari-it.com/python-os-walk/