Python Tkinter按钮命令功能不可用'；我不能完成它的任务

我正在尝试创建一个需要您登录的程序，但是命令的

def

中的

if

语句似乎不起作用，我不知道为什么

---

要使其工作，您需要在单击按钮时获取值，而不是在文本框初始化时获取值。因此，如果您将登录功能更改为以下内容，则您的程序应按预期运行

from tkinter import *

#Windows
logWin = Tk()
mainWin = Tk()
srchWin = Tk()
NTWin = Tk()

#Variables
userName="123"
password="123"
logFail = ""
userBox = Entry(logWin)
passBox = Entry(logWin)
EU = userBox.get()
EP = passBox.get()

#General Window
mainWin.withdraw()
srchWin.withdraw()
NTWin.withdraw()

#Command
def loginCmd():
    if EU == userName and EP == password:
        print ("hello")
    else:
        print("no")


#Login Window
logWin.title("Login")
logWin.geometry("200x70")

userBox.grid(row=0,column=1)
passBox.grid(row=1,column=1)

userLbl = Label(logWin,text="Username:")
userLbl.grid(row=0,column=0)
passLbl = Label(logWin,text="Password:")
passLbl.grid(row=1,column=0)
failLbl = Label(logWin,text=logFail)
failLbl.grid(row=2,column=0)

logBtn = Button(logWin,text="Login",command=loginCmd)
logBtn.grid(row=2,column=1)


mainloop()

def loginCmd():
    if userBox.get() == userName and passBox.get() == password:
        print("hello")
    else:
        print("no")