如何在函数内部从tkinter文本小部件获取输入

Question

对编码相对较新，目前我在python中使用tkinter，我在一个函数中使用一个文本小部件，并希望将文本框中的输入发送到另一个函数。我的全局变量表示在模块级别未定义，那么如果它在函数中，我如何在模块级别定义它呢？

当我按下发送电子邮件按钮时，我会收到此错误消息"NameError:name'user_message_entry'未定义">

有什么建议吗？非常感谢！

最小再现：

import tkinter as tk
root = tk.Tk()
root.geometry("500x500")

def send_email():
global user_message_entry
subject = ":)"
body = user_message_entry.get("1.0", "end")
message = f"subject: {subject}nn {body}"
print(message)

def feedback():
feedback_window = tk.Toplevel()
feedback_window.geometry("690x650")
message_frame = tk.Frame(feedback_window)
message_frame.grid(row=0, column=0, columnspan=3)
user_message_entry = tk.Text(message_frame, height=10, width=60)
user_message_entry.grid(row=0, column=0)
send_email_button = tk.Button(feedback_window, command=send_email,
height=20, width=20, bg="yellow", text="send email")
send_email_button.grid(row=1, column=0)

open_feedback_button = tk.Button(root, command=feedback, height=20, width=20, bg="yellow", text="open feedback window")
open_feedback_button.grid(row=1, column=0)
root.mainloop()

Answer 1

您可以使用面向对象的方法使访问sympler，另一个选项也可以使用globals((使变量全局

单向

globals()['user_message_entry'] = tk.Text(message_frame, height=10, width=60)
.... 

从另一个函数你可以调用

body = globals()['user_message_entry'].get("1.0", "end")

第二路

面向对象编程适用于各种类型的问题解决，因此您也可以使用类

import tkinter as tk
class CBased:
def __init__(self, master, *args, **kwargs):
super(CBased, self).__init__(*args, *kwargs)
self.master = master
master.geometry("500x500")
self.open_feedback_button = tk.Button(master, command=self.feedback, height=20, width=20, bg="yellow", text="open feedback window")
self.open_feedback_button.grid(row=1, column=0)
def send_email(self):
subject = ":)"
body = self.user_message_entry.get("1.0", "end")
message = f"subject: {subject}nn {body}"
print(message)

def feedback(self):
self.feedback_window = tk.Toplevel()
self.feedback_window.geometry("690x650")
self.message_frame = tk.Frame(self.feedback_window)
self.message_frame.grid(row=0, column=0, columnspan=3)
self.user_message_entry = tk.Text(self.message_frame, height=10, width=60)
self.user_message_entry.grid(row=0, column=0)
self.send_email_button = tk.Button(self.feedback_window, command=send_email,
height=20, width=20, bg="yellow", text="send email")
self.send_email_button.grid(row=1, column=0)
def main():
root        = Tk()
myobj       = CBased(root)
root.mainloop()
if __name__ == "__main__":main()

通过这种方式，你可以通过self.xyz 调用每一个项目