Question

我希望这个也一直循环，直到输入正确的文件名。例如，如果我有一个名为test.txt的文件，那么我希望问题循环直到找到正确的名称。反正有吗？

def validate():
    file = ""
    flag = True
    while flag:
        try:
            file = input("Enter the name of the file: ")
            # If I leave false then it will quit the loop even if the file name 
            # does not exist. I only want it to exit once the correct file name 
            # is entered. Note the txt file will be created by the user so it
            # can always change.
            flag = False
        except FileNotFoundError:
            flag = True
    return file

Answer 1

执行此操作的正确方法是使用path.isfile

import os

def validate():
    while True: #loop until the inputed filename is an existing file
        filename = input("Enter the name of the file: ")
        if os.path.isfile(filename): #filename refers to a file that exists and is not a folder
             return filename

Answer 2

这会有用吗？实际上打开文件以触发异常

def validate():
    file = ""
    flag = True
    while flag:
        try:
            file = input("Enter the name of the file: ")
            with open(file) as fh:
                # do something with fh if you want
            flag = False
        except FileNotFoundError:
            flag = True
    return file

Here's有关在python中读取和写入文件的更多信息

Python：尝试/除外

2 个答案: