Python 名称错误：名称'；fooAlpha和#x27；没有定义

运行脚本时，我得到了

名称错误：名称“fooAlpha”未定义。
从研究来看，我相信这是因为我没有在脚本的早期声明fooAlpha。然而，即使将fooAlpha=”“放在第22行附近，我仍然会得到一个错误。
我觉得我对python缺乏一点了解，无法克服这个错误。请告诉我如何解决这个问题

#   CAESAR CIPHER - PART 6 
#   Add a GUI
#   - by JeffGames
#   
#
#
# ToDo: 
# 1. Add JeffGames icon
# 2. Handle spaces in the string


# Import tkinter, our GUI framework
from tkinter import * # Import tkinter, our GUI framework

root = Tk()

# Variables used by the main program.
alphabet01 = 'GjlZCMaQKU"/-Xf$£\\mrw:>H(%Fo&tD<!gJLzbiSxBcT,dqPYy=*OA~_?^.)E;evN+R#k\'@hnIuVWsp'
alphabet02 = 'hkS*F>ucL/l-)VPB£iR\\ZUdI\'CQ$z(@?=f<ta:m#Wvp;~n!Yg."^sxMHNKDwybjr_,O%oq+TJGXAEe&'
alphabet03 = '(OIce$TnM=JvF?j<&X+S>i\\h"EY\'dK£,lq!Z@~QmbyD-wUWNsrV^H:fB.aPpkL_otC/);RzAGxg%*#u'

# Define what happens when the go button is clicked

def clickAlpha():
    print("Alphabet from clickAlpha = ", algo.get()) # Calls algo and prints its value
    myAlpha = algo.get()
    print("myAlpha = ", myAlpha) # debug printing
    if myAlpha == "Alpha1":
        print(alphabet01) # debug printing
        fooAlpha = alphabet01
    elif myAlpha == "Alpha2":
        print(alphabet02) # debug printing
        fooAlpha = alphabet02
    else:
        print(alphabet03) # debug printing
        fooAlpha = alphabet03


def clickEncrypt():
    msgEncrypt = msgInput.get()
    msgEncrypt = str(msgEncrypt)
    #print(msgEncrypt) # Used for debugging
    caesarShift = cesar.get()
    caesarShift = int(caesarShift)
    useAlpha = fooAlpha
    useAlpha = str(useAlpha)
    print(useAlpha) # Used for debugging
    newMessage = ""

    for character in msgEncrypt:
        if character in useAlpha:
            position = useAlpha.find(character) 
            # NB: len(alphabet) handles a list of any length
            newPosition = (position + caesarShift)%len(useAlpha) 
            newCharacter = useAlpha[newPosition]
            newMessage += newCharacter
            #Put the new message into the message output field        
            msgOutput.delete(0, END) # Clear the output field after GO is clicked
            # Ans = str(newMessage) # Read message for putting into the output field
            msgOutput.insert(0, newMessage) #(0, Ans) # Put the message from input field into

def clickDecrypt():
    print("Decrypt pressed")
    msgEncrypt = msgInput.get()
    msgEncrypt = str(msgEncrypt)
    #print(msgEncrypt) # Used for debugging
    caesarShift = cesar.get()
    caesarShift = int(caesarShift)
    useAlpha = fooAlpha # Hard coding the algo
    useAlpha = str(useAlpha)
    print(useAlpha) # Used for debugging
    newMessage = ""

    for character in msgEncrypt:
        if character in useAlpha:
            position = useAlpha.find(character) 
            # NB: len(alphabet) handles a list of any length
            newPosition = (position - caesarShift)%len(useAlpha) 
            newCharacter = useAlpha[newPosition]
            newMessage += newCharacter
            #Put the new message into the message output field        
            msgOutput.delete(0, END) # Clear the output field after GO is clicked
            # Ans = str(newMessage) # Read message for putting into the output field
            msgOutput.insert(0, newMessage) #(0, Ans) # Put the message from input field into

def moveCaesar(sld): # A variable must be in here for the function to work
    print("Shift = ", cesar.get()) # Calls cesar variable and prints its value

def clickClear():
    msgInput.delete(0, END)
    msgOutput.delete(0, END)
    print("Cleared all messages")

def clickCopy():
    return # Will eventually copy the decrypted or encrypted text to clipboard

def clickQuit(): # Created to have a pop-up to confirm quit.
    btnExit(command=root.quit)

# Set up for the Alphabet being used. Alphabet 1 is default
algo = StringVar()
algo.set("Alpha1") # Sets Alphabet 1 as default
print("Initial alphabet: ", algo.get()) # Calls algo.set and prints its value

# Set up for the Casar shift. 0 is the default
cesar = IntVar()
cesar.set(1)
print("Initial shift: ", cesar.get()) # Calls cesar variable and prints its value

# SET UP THE CANVAS
root.title("Caesar Cipher by JeffGames")


#   ---------------------------------------------------
#   SET UP THE BUTTONS, Message boxes, and input areas
#   ---------------------------------------------------

# Welcome message
welcFrame = LabelFrame(root, padx=10, pady=10, bg='blue')
lblWelcome = Label(welcFrame, text="Welcome to the Caesar Cipher program", bg='blue', fg='white') 

# Input message box with a heading instructing user to paste or type message
lblMsgIn = Label(root, text="STEP 1 - Type or paste your message in the box below.")
msgInput = Entry(root)

# Alphabet choices
alphaFrame = LabelFrame(root, padx=10, pady=10, bg='green')
lblAlphaChoice = Label(alphaFrame, text=" STEP 2 - Now choose your encryption algo")
btnAlpha1 = Radiobutton(alphaFrame, text="Alphabet 1", variable=algo, value="Alpha1", command=clickAlpha) 
btnAlpha2 = Radiobutton(alphaFrame, text="Alphabet 2", variable=algo, value="Alpha2",command=clickAlpha) 
btnAlpha3 = Radiobutton(alphaFrame, text="Alphabet 3", variable=algo, value="Alpha3",command=clickAlpha) 

# Caesar shift slider
caesarFrame = LabelFrame(root, padx=10, pady=10, bg='red')
lblCaesar = Label(caesarFrame, text=" STEP 3 - Now set your Caesar Shift")
sldrCaesar = Scale(caesarFrame, from_=0, to=80, variable=cesar, orient=HORIZONTAL, command=moveCaesar)

# Encrypt / Decrypt user choices
cryptFrame = LabelFrame(root, padx=10, pady=10, bg='pink')
lblCryptMsg = Label(cryptFrame, text="STEP 1 - Press a button to Encrypt or Decrypt a message", padx=5, pady=5)
btnCrypt1 = Button(cryptFrame, text="Encrypt", command=clickEncrypt)
btnCrypt2 = Button(cryptFrame, text="Decrypt", command=clickDecrypt) 

#Output box
msgOutput = Entry(root)

# Clear, Copy to clipboard, and Exit  buttons
btnClear = Button(root, text="Clear All", command=clickClear)   
btnCopy = Button(root, text="Copy to clipboard", command=clickCopy)
btnExit = Button(root, text="Quit", command=root.quit)

#   -----------------------------
#   PUT THE BUTTONS ON THE SCREEN
#   -----------------------------

# ROW 0 - Welcome message
welcFrame.grid(row=0, columnspan=3, sticky=W+E)
lblWelcome.grid(row=0, column=0, columnspan=3)

# ROW 1 & 2 - User's Message input heading and area
lblMsgIn.grid(row=1, column=0, columnspan=3)
msgInput.grid(row=2, column=0, columnspan=3, sticky=W+E)

# ROW 3 & 4 - Choose Alphabet button and message placement
alphaFrame.grid(row=3, columnspan=3, sticky=W+E)
lblAlphaChoice.grid(row=3, column=0, columnspan=3, sticky=W)
btnAlpha1.grid(row=4, column=0)
btnAlpha2.grid(row=4, column=1)
btnAlpha3.grid(row=4, column=2)

# ROW 5 & 6 Caesar shift slider
caesarFrame.grid(row=5, columnspan=3, sticky=W+E)
lblCaesar.grid(row=5, column=0, columnspan=3, sticky=W)
sldrCaesar.grid(row=6, column=0, columnspan=3, sticky=W+E)

# ROW 7 & 8 - Encrypt Decrypt button and message placement
cryptFrame.grid(row=7, columnspan=3, sticky=W+E)
lblCryptMsg.grid(row=7, column=0, columnspan=3, sticky=W)
btnCrypt1.grid(row= 8, column=0)
btnCrypt2.grid(row= 8, column=1)

# ROW 0 - User's Message ouput heading and area
msgOutput.grid(row=9, column=0, columnspan=3, sticky=W+E)

# ROW 10 - Clear Messages & Copy to clipboard, Exit program button placement
btnClear.grid(row=10, column=0)
btnCopy.grid(row=10, column=1)
btnExit.grid(row=10, column=2)

# tkinter mainloop
root.mainloop()

凯撒密码-第6部分
#添加GUI
#-杰斐逊游戏公司
#   
#
#
#待办事项：
# 1. 添加游戏图标
# 2. 处理字符串中的空格
#导入tkinter，我们的GUI框架
从tkinter import*#import tkinter，我们的GUI框架
root=Tk（）
#主程序使用的变量。
alphabet01='GjlZCMaQKU/-Xf$。\\mrw:>H（%Fo&tDucL/l-）VPB.iR\\ZUdI'CQ$z（@？=f您正在使用
fooAlpha
内部
单击加密
和
单击解密
而不定义它，首先定义它，然后在更改它的函数中使用
全局
关键字
（单击Alpha）
。代码的第一部分应该是：

# Define what happens when the go button is clicked
fooAlpha = ''                 # <========= Add this
def clickAlpha():
    global fooAlpha           # <========= Add this
    # rest of code

#定义单击go按钮时发生的情况
fooAlpha=''#
fooAlpha
是
clickAlpha（）
函数中的一个局部变量。在该函数之外无法访问它。请阅读Add
fooAlpha='"
在其他变量之后，然后将
全局fooAlpha
放在
单击alpha
的开头。感谢大家的帮助。我认为我没有尝试同时添加
fooAlpha
和声明
全局fooAlpha
。不应该鼓励人们使用
全局
。这是一种糟糕的做法将其放入函数中，这样它们就可以明显地访问顶级变量，或者将所有函数包装在一个存储共享变量的类中。这不起作用-
global
必须在修改变量的范围内使用。其他地方根本不需要它。@Ekhumaro，你是对的，我没有把所有函数都用到ee如果它正在更改或未更改，您可以将其注释掉。@faressalem感谢您编辑代码。请将“傻瓜Alpha”改为“fooAlpha”这可能会造成复制/粘贴错误。不应鼓励人们使用
global
。这是一种不好的做法。要么将其传递给函数，使它们可以明显地访问顶级变量，要么将所有函数包装在一个存储共享变量的类中。