TypeError:不支持的+操作数类型：“instance”和“instance”Python 2.7

Question

我试图使用Tkinterface来制作一个简单的计算器，可以进行加法、减法、乘法和除法运算，但是我有一个问题，当我试图执行我的程序时，我得到了这个错误：

TypeError:不支持+的操作数类型：“instance”和“instance”

我个人不知道为什么会发生这种情况，我四处寻找，发现了类似错误的问题，但不是“实例”和“实例”。 这是我的代码：

#!/usr/bin/python2.7

#Imports necessary modules

from Tkinter import *
#import Tkinter.messagebox
import time as t
import os

#End of importing

#Defines interface

calc = Tk()
calc.title("GUI Calculator")
calc.geometry("500x350+200+200")

#End of interface definition

#Defines methods

def add(val1, val2):
    global ans
    ans = int(val1 + val2)
    return ans

def sub(val1, val2):
    global ans
    ans = int(val1 - val2)
    return ans

def mul(val1, val2):
    global ans
    ans = int(val1 * val2)
    return ans

def div(val1, val2):
    global ans
    ans = float(val1 % val2)
    return ans

#End of method defining

#Heading
but1Text = StringVar()
but1Text.set("Welcome to the GUI Calculator")
label1 = Label(calc, textvariable=but1Text, height=2)
label1.pack()

#Instruction 1
but2Text = StringVar()
but2Text.set("Enter value number one!")
label2 = Label(calc, textvariable=but2Text, height=2)
label2.pack()

#Val 1 input
num1 = IntVar()
val1 = Entry(calc, textvariable=num1)
val1.pack()

#Instruction 2
but3Text = StringVar()
but3Text.set("Enter value number one!")
label3 = Label(calc, textvariable=but2Text, height=2)
label3.pack()

#Val 2 input
num2 = IntVar()
val2 = Entry(calc, textvariable=num2)
val2.pack()

#Operation selector

but4Text = StringVar()
but4Text.set(None)
operator = Radiobutton(calc, text = "Addition", value = "Add", variable = but4Text,command = add(val1,val2)).pack()
operator = Radiobutton(calc, text = "Subtract", value = "Sub", variable = but4Text,command = sub(val1,val2)).pack()
operator = Radiobutton(calc, text = "Multiply", value = "Mul", variable = but4Text,command = mul(val1,val2)).pack()
operator = Radiobutton(calc, text = "Divide",   value = "Div", variable = but4Text,command = div(val1,val2)).pack()

#Answer
but5Text = StringVar()
but5Text.set("Answer=")
label4 = Label(calc, textvariable=but5Text, height=2)
label4.pack()

#Answer
but6Text = StringVar()
but6Text.set(ans)
label5 = Label(calc, textvariable=but6Text, height=2)
label5.pack()

#Mainloop
calc.mainloop()

以下是完整的错误：

Traceback (most recent call last):
  File "./tkCalc.py", line 76, in <module>
    operator = Radiobutton(calc, text = "Addition", value = "Add", variable = but4Text,command = add(val1,val2)).pack()
  File "./tkCalc.py", line 24, in add
    ans = int(val1 + val2)
TypeError: unsupported operand type(s) for +: 'instance' and 'instance'

Answer 1

您需要对控件实例中文本的数值（int或float）执行操作，而不是对控件本身执行操作。

尝试：

def add(num1, num2):
    global ans
    ans = int(num1.get() + num2.get())
    return ans

以及

operator = Radiobutton(calc, text = "Addition", value = "Add", variable = but4Text,command = add(num1, num2)).pack()

所以add按钮传递变量，函数从变量中获取值。