另一个可能的选项是检查文件名是否在目录中使用 os.listdir():

import os
if 'foo.txt' in os.listdir():
    # Do things

如果是真相,如果是虚假,如果不是真相。

如果文件是要打开的,您可以使用以下技术之一:

with open('somefile', 'xt') as f: # Using the x-flag, Python 3.3 and above
    f.write('Hello\n')

if not os.path.exists('somefile'): 
    with open('somefile', 'wt') as f:
        f.write("Hello\n")
else:
    print('File already exists!')

注意:此查找一个文件或指定的名称的目录。

查看文件或目录存在

你可以遵循这三种方式:

使用 isfile( )

注意1: os.path.isfile 仅用于文件

import os.path
os.path.isfile(filename) # True if file exists
os.path.isfile(dirname) # False if directory exists

二、使用存在

注意2: os.path.exists 用于文件和目录

import os.path
os.path.exists(filename) # True if file exists
os.path.exists(dirname) # True if directory exists

pathlib.Path 方法(包含在 Python 3+ 中,可与 Python 2 的 pip 安装)

from pathlib import Path
Path(filename).exists()

使用 os.path.exist 查看文件和目录:

import os.path
os.path.exists(file_path)

使用 os.path.isfile 仅查看文件(注:以下是符号链接):

os.path.isfile(file_path)

这就是我如何在一个文件夹中找到一个文件列表(在这些图像中)并在一个文件夹中搜索它(与子文件夹):

# This script concatenates JavaScript files into a unified JavaScript file to reduce server round-trips

import os
import string
import math
import ntpath
import sys

#import pyodbc

import gzip
import shutil

import hashlib

# BUF_SIZE is totally arbitrary, change for your app!
BUF_SIZE = 65536  # Let’s read stuff in 64 kilobyte chunks

# Iterate over all JavaScript files in the folder and combine them
filenames = []
shortfilenames = []

imgfilenames = []
imgshortfilenames = []

# Get a unified path so we can stop dancing with user paths.
# Determine where files are on this machine (%TEMP% directory and application installation directory)
if '.exe' in sys.argv[0]: # if getattr(sys, 'frozen', False):
    RootPath = os.path.abspath(os.path.join(__file__, "..\\"))

elif __file__:
    RootPath = os.path.abspath(os.path.join(__file__, "..\\"))

print ("\n storage of image files RootPath: %s\n" %RootPath)

FolderPath = "D:\\TFS-FARM1\\StoneSoup_STS\\SDLC\\Build\\Code\\StoneSoup_Refactor\\StoneSoupUI\\Images"
print ("\n storage of image files in folder to search: %s\n" %FolderPath)

for root, directories, filenames2 in os.walk(FolderPath):
    for filename in filenames2:
        fullname = os.path.join(root, filename)
        filenames.append(fullname)
        shortfilenames.append(filename)

for i, fname in enumerate(shortfilenames):
        print("%s - %s" % (i+1, fname))

for root, directories, filenames2 in os.walk(RootPath):
    for filename in filenames2:
        fullname = os.path.join(root, filename)
        imgfilenames.append(fullname)
        imgshortfilenames.append(filename)

for i, fname in enumerate(imgshortfilenames):
        print("%s - %s" % (i+1, fname))

for i, fname in enumerate(imgshortfilenames):
        if fname in shortfilenames:
            print("%s - %s exists" % (i+1, fname))
        else:
            print("%s - %s ABSENT" % (i+1, fname))

使用:

import os

# For testing purposes the arguments defaulted to the current folder and file.
# returns True if file found
def file_exists(FOLDER_PATH='../', FILE_NAME=__file__):
    return os.path.isdir(FOLDER_PATH) \
        and os.path.isfile(os.path.join(FOLDER_PATH, FILE_NAME))

它基本上是一个文件夹检查,然后使用 os.path.join 使用适当的目录分离器进行文件检查。