如何从 Entry 小部件中获取文本？ [复制]答案

【问题标题】：How do i get text from an Entry widget? [duplicate]如何从 Entry 小部件中获取文本？ [复制]
【发布时间】：2021-07-09 02:42:41
【问题描述】：

我刚开始学习python，想做一个简单的登录GUI。我尝试按照教程进行操作，但由于某种原因，我的代码总是出错。这是错误：第 18 行，登录 print(f"我的用户名是 {username.get()} 我的密码是 {password.get()}") AttributeError: 'NoneType' 对象没有属性 'get'

from tkinter import *

main_window = Tk()



# ---------- LABELS ----------
Label(main_window, text = "Username: ").grid(row = 0, column = 0)
Label(main_window, text = "Password: ").grid(row = 1, column = 0)

# ---------- TEXT INPUT ----------
username = Entry(main_window, width = 50, borderwidth = 3.5).grid(row = 0, column = 1)
password = Entry(main_window, width = 50, borderwidth = 3.5, show = "*").grid(row = 1, column = 1)

# ---------- METHODS ----------
def sign_in():
    print(f"My username is {username.get()} and my password is {password.get()}")

# ---------- BUTTON ----------
Button(main_window, text = "Sign In", command = sign_in).grid(row = 2, column = 1)

# ---------- MAIN LOOP ----------
main_window.mainloop()

【问题讨论】：

标签： python python-3.x tkinter widget

【解决方案1】：

问题是当您定义用户名和密码时，您也在对其进行网格化。相反，您应该将用户名和密码条目分别网格化，如下所示：

    from tkinter import *

    main_window = Tk()
    
    
    
    # ---------- LABELS ----------
    Label(main_window, text = "Username: ").grid(row = 0, column = 0)
    Label(main_window, text = "Password: ").grid(row = 1, column = 0)
    
    # ---------- TEXT INPUT ----------
    username = Entry(main_window, width = 50, borderwidth = 3.5) # Remove grid here
    password = Entry(main_window, width = 50, borderwidth = 3.5, show = "*")

    username.grid(row=0, column=1) # grid Entry's seperately
    password.grid(row=1, column=1)
    
    # ---------- METHODS ----------
    def sign_in():
        print(f"My username is {username.get()} and my password is {password.get()}")
    
    # ---------- BUTTON ----------
    Button(main_window, text = "Sign In", command = sign_in).grid(row = 2, column = 1)
    
    # ---------- MAIN LOOP ----------
    main_window.mainloop()

【讨论】：

“另外，你不能在 tkinter 中改变 Entry 对象的宽度” - 是的，你可以。你是说身高吗？