a = var.get() ：这里 a 是函数中的局部变量。

a = 0
def sel():
    a = 2
    print("a from sel:", a)
sel()
print("a:", a)

输出：

a from sel: 2
a: 0

或者，您可以 a 全局变量。

from tkinter import *

global scale_value

# set default

scale_value = 0

def save_scale_value(event):
    global scale_value
    # save the current value while the program is running
    scale_value = event.widget.get()
    print(f"Saved: {scale_value}")

def sel():
    # reuse a variable in another function
    global scale_value
    print(f"global scale_value: {scale_value}")
    selection = "Value = " + str(var.get())
    label.config(text = selection)

root = Tk()
var = DoubleVar()

scale = Scale( root, variable = var )
scale.pack(anchor=CENTER)

button = Button(root, text="Get Scale Value", command=sel)
button.pack(anchor=CENTER)

label = Label(root)
label.pack()

scale.bind("<ButtonRelease>", save_scale_value)
root.mainloop()

# this will only print after the window is closed, when the root is destroyed

print(scale_value)

如果您使用的是类，则可以将此变量设为类示例的数据属性（例如， self.a ).