How to check whether a file exists or not in python?

Question

I have to parse a file if it exists in the current directory. How do I do it and what is the simple and most efficient way to do this?

Answer 1

What you are looking at can be done easily by using isfile function of os.path.
Official documentation of os.path.isfile - Return True if path refers to a directory entry that is a symbolic link. Always False if symbolic links are not supported by the Python runtime.

It can be done as follows -

>>> import os

>>> os.path.isfile
<function isfile at 0x0205B1F0>

>>> os.path.isfile('C:\Python27\README.txt')
True

>>> os.path.isfile('README.txt')
True

>>> os.path.isfile('./README.txt')
True

>>> os.path.isfile('FAKENAME.txt')
 False

Above code is the output of python.exe and there is a file README.txt adjacent to it.
Second command is just to show that os.path.isfile is a function.
We can pass the complete path or the absolute path to this function(as show in command 3, 4 and 5).

Comments

I found an update guide on how to check if a file exists with python here: http://tutorials.technology/tutorials/08-How-to-check-that-file-exists-with-Python.html

Answer 2

import os
dirname = "temp"
filename = "my_file"
#check directory exists
if(os.path.exists(dirname)):
print("Directory Exists")
else:
print("Directory does not exists")

#check file exists
if(os.path.exists(filename)):
print("File Exists")
else:
print("File does not exists")

Full source...file exist