为什么字典在这个while循环中填充，但在循环之外它是“空的”？

Question

我正在尝试通过收集用户关于文件夹名称和他/她想要自动放置在该文件夹中的扩展名的输入来使用 Python 自动化文件管理。

创建字典以将文件夹名称保存为字符串（字典键）并将扩展名保存为字符串列表后，用户填充每个列表，我在填充字典时将它们结合起来。

问题： 我能够使用上述信息填充循环内部的字典，但我已经尝试在 while 循环之外打印字典，但它没有不工作。因此，我的程序无法在字典中没有值的情况下工作。 能否请您检查一下为什么我在退出 while 循环后无法保留字典中的信息？

模拟：程序一直运行到循环的最后部分（见下图），然后关闭窗口，什么也没有发生。

第一部分代码：

import os

# Library that helps to find path of the items
from pathlib import Path

# Create list variables
namefiles = []
nameextension1 = []
flag = True
uanswer = ""
count = 0
count2 = 1
flag2 = True
extbreak = ""

# Create dictionaries to organize the folders
Subdirectories = {}

# This is the while-loop to collect the input from the user and populate the lists/dictionary:*

# Collecting input from the users
while flag:
    flag2 = True
    uanswer = input("\nWould you like to create a Folder in the Library?\n Please, type 'Y' for 'yes'\n or 'N' for 'no':  ")
    if uanswer == "N":
        flag = False
    elif uanswer == "Y":
        namefiles.append(input("\nType in the name of the folder:  "))
        while flag2:
            nameextension1.append(input("\nType in the name of the extension.\n EX: .pdf:  "))
            extbreak = input("\nWould you like to add another extension?\n Please, type 'Y' for 'yes'\n or 'N' for 'no':  ")
            if extbreak == "N":
                flag2 = False
    else:
        print("\nPlease try again!!!")
    # Populating the dictionary
    Subdirectories[namefiles[count]] = nameextension1
    print (Subdirectories)
    count += 1
    # Cleaning the lists to use for the next extension
    nameextension1 = []

# I don't know if this is relevant, but the following step after the while-loop is this:*

file_formats = {file_format: directory
                for directory, file_formats in Subdirectories.items()
                for file_format in file_formats}

感谢您的支持，如果我的解释不是很清楚，我很抱歉。 如果您有任何问题，请随时发表评论，我会提供尽可能多的细节:)

PS：母亲节快乐！

Answer 1

我刚刚在flag = Flase之后添加了一个休息：

import os

# Library that helps to find path of the items
from pathlib import Path

# Create list variables
namefiles = []
nameextension1 = []
flag = True
uanswer = ""
count = 0
count2 = 1
flag2 = True
extbreak = ""

# Create dictionaries to organize the folders
Subdirectories = {}

# This is the while-loop to collect the input from the user and populate the lists/dictionary:*

# Collecting input from the users
while flag:
    flag2 = True
    uanswer = input("\nWould you like to create a Folder in the Library?\n Please, type 'Y' for 'yes'\n or 'N' for 'no':  ")
    if uanswer == "N":
        flag = False
        break
    elif uanswer == "Y":
        namefiles.append(input("\nType in the name of the folder:  "))
        while flag2:
            nameextension1.append(input("\nType in the name of the extension.\n EX: .pdf:  "))
            extbreak = input("\nWould you like to add another extension?\n Please, type 'Y' for 'yes'\n or 'N' for 'no':  ")
            if extbreak == "N":
                flag2 = False
    else:
        print("\nPlease try again!!!")
    # Populating the dictionary
    Subdirectories[namefiles[count]] = nameextension1
    print (Subdirectories)
    count += 1
    # Cleaning the lists to use for the next extension
    nameextension1 = []

# I don't know if this is relevant, but the following step after the while-loop is this:*

file_formats = {file_format: directory
                for directory, file_formats in Subdirectories.items()
                for file_format in file_formats}

Answer 2

当用户决定完成该过程时，代码给出了IndexError。我刚刚用

替换了flags

while True:
    ...
    if something:
        break

而且效果很好。

import os

# Library that helps to find path of the items
from pathlib import Path

# Create list variables
namefiles = []
nameextension1 = []
flag = True
uanswer = ""
count = 0
count2 = 1
flag2 = True
extbreak = ""

# Create dictionaries to organize the folders
Subdirectories = {}

# This is the while-loop to collect the input from the user and populate the lists/dictionary:*

# Collecting input from the users
while True:
    uanswer = input("\nWould you like to create a Folder in the Library?\n Please, type 'Y' for 'yes'\n or 'N' for 'no':  ")
    if uanswer == "N":
        break
    elif uanswer == "Y":
        namefiles.append(input("\nType in the name of the folder:  "))
        while True:
            nameextension1.append(input("\nType in the name of the extension.\n EX: .pdf:  "))
            extbreak = input("\nWould you like to add another extension?\n Please, type 'Y' for 'yes'\n or 'N' for 'no':  ")
            if extbreak == "N":
                break
    else:
        print("\nPlease try again!!!")
    # Populating the dictionary
    Subdirectories[namefiles[count]] = nameextension1
    print (Subdirectories)
    count += 1
    # Cleaning the lists to use for the next extension
    nameextension1 = []

print("*"*50)
print(Subdirectories)