我正在使用一个聊天应用程序，但是我收到一个错误消息，即使我设计了变量也没有定义，我知道我可能必须重组一些东西，但是我不确定从哪里开始，这里的代码引起问题
import socket
import select
import errno
import sys
import threading
from tkinter import *
HEADER_LENGTH = 10
IP = socket.gethostbyname("0.0.0.0")
PORT = 1234
class inputNameWin():
def __init__(self):
self.window = Tk()
self.window.title("login")
self.inputLabel = Label(self.window, text="Type in your username, then click connect")
self.inputLabel.grid(row=0, column=1)
self.inputName = Entry(self.window, width="10")
self.inputName.grid(row=1, column=0, columnspan=2)
self.connectButton = Button(self.window, text="CONNECT", command= lambda : self.checkName(self.inputName.get()))
self.connectButton.grid(row=2, column=0, columnspan=2)
self.window.mainloop()
def checkName(self, name):
name = name.strip()
if len(name) <= 3 :
self.inputLabel['text'] = f"Username {name} is too short! Try another"
elif len(name) >= 15:
self.inputLabel['text'] = f"Username {name} is too long! Try another"
else:
self.window.destroy()
start(name)
class mainWin():
def __init__(self, username):
self.username = username
self.mainWindow = Tk()
self.mainWindow.title(f"Chatty.py client [NO CONNECTION] NAME = {self.username}")
self.mainWindow.configure(bg="white")
self.padSizeX = 5
self.padSizeY = 60
self.status = Label(self.mainWindow, text=f"Username : {self.username} [NO CONNECTION]", fg="black", bg="white")
self.status.grid(row=0, column=0, columnspan=2)
self.messagEntry = Entry(self.mainWindow, fg="black", bg="white")
self.messageSend = Button(self.mainWindow, text="Send", command= lambda : connection.sendMessage(self.messagEntry.get()), fg="green", bg="white", activebackground="white", activeforeground="black")
self.messagEntry.grid(row=2, column=0, columnspan=2)
self.messageSend.grid(row=3, column=0, columnspan=2)
self.incoming = Listbox(self.mainWindow, fg="green", bg="white", width=50, height=25, selectbackground="blue", highlightcolor="green2")
self.incoming.grid(row=1, column=0)
self.outgoing = Listbox(self.mainWindow, fg="blue", bg="white", width=50, height=25, selectbackground="green", highlightcolor="green2")
self.outgoing.grid(row=1, column=1)
class connectionHandler():
def __init__(self, username):
self.client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.client_socket.connect((IP, PORT))
self.client_socket.setblocking(False)
self.username = username.encode("utf-8");
self.username_header = f'{len(username):<{HEADER_LENGTH}}'
self.username_header = self.username_header.encode('utf-8')
self.client_socket.send(self.username_header + self.username)
main = threading.Thread(target=self.main)
main.start()
def sendMessage(self,message):
if(message):
try:
message = str(message)
try:
type_, data = message.split("$")
if(type_ == "message"):
messageOutput = f"message${data}"
GUI.incoming.insert(END, "")
GUI.outgoing.insert(END, f"{data} << {self.username}")
else:
print(f"invalid type {type_}")
except:
messageList = []
type_ = messageList[1]
messageList.remove(type_)
for part in messageList:
messageOutput = f"{message}{part}"
messageOutput = messageOutput.encode("utf-8")
message_header = f"{len(messageOutput):<{HEADER_LENGTH}}".encode('utf-8')
GUI.client_socket.send(message_header + messageOutput)
GUI.incoming.insert(END, "")
self.outgoing.insert(END, f"{messageOutput} << {self.username}")
except:
message = str(message)
messageOutput = f"message${message}".encode("utf-8")
message_header = f"{len(messageOutput):<{HEADER_LENGTH}}".encode("utf-8")
self.client_socket.send(message_header + messageOutput)
GUI.incoming.insert(END, "")
GUI.outgoing.insert(END, f"{messageOutput} << {self.username}")
def main(self):
while True:
try:
while True:
username_header = self.client_socket.recv(HEADER_LENGTH)
if(not len(username_header)):
print("connection closed by server")
sys.exit()
username_lenght = int(username_header.decode("utf-8").strip())
username = client_socket.recv(username_lenght).decode("utf-8")
message_header = client_socket.recv(HEADER_LENGTH)
message_length = int(message_header.decode("utf-8").strip())
messageRaw = client_socket.recv(message_length).decode("utf-8")
type_, message = messageRaw.split("$")
if(type_ == "message"):
print(f"{username} >> {message}")
elif(type_ == "cmd"):
print("got cmd")
if(username == "sever"):
print("recieved server command")
except IOError as e:
if(e.errno != errno.EAGAIN and e.errno != errno.EWOULDBLOCK):
print("READ ERR",str(e))
sys.exit()
continue
except Exception as e:
print("Error".str(e))
sys.exit()
def start(username):
connection = connectionHandler(username)
GUI = mainWin(username)
GUI.mainWindow.mainloop()
loginWin = inputNameWin()
很抱歉，您无法阅读一百多行代码。我收到的错误是
Exception in Tkinter callback
Traceback (most recent call last):
File "/home/kali/anaconda3/lib/python3.7/tkinter/__init__.py", line 1705, in __call__
return self.func(*args)
File "client.py", line 54, in <lambda>
self.messageSend = Button(self.mainWindow, text="Send", command= lambda : connection.sendMessage(self.messagEntry.get()), fg="green", bg="white", activebackground="white", activeforeground="black")
NameError: name 'connection' is not defined
我需要使连接成为局部变量，还是只需要取消此结构并重做我要处理的方式？
Python在词法上（也称为静态）范围内，而不是动态范围内。这意味着connection中使用的mainwin.__init__必须是global变量，因为它不是__init__的局部变量，并且全局范围是最接近的封闭范围。不过，您正在start函数中将其定义为local变量。
最快的解决方法是在connection中全局分配给start：
def start(username):
global connection
connection = connectionHandler(username)
GUI = mainWin(username)
GUI.mainWindow.mainloop()
一种更好的解决方案是将所需的对象作为mainWin.__init__的参数传递，尽管这需要对定义进行其他小的更改，因为您希望回调函数使用传递给__init__的值，而不是[ C0]作为自由变量。
首先，
connection然后，
def start(username):
connection = connectionHandler(username)
GUI = mainWin(username, connection)
GUI.mainWindow.mainloop()