python计算器：检查输入有效性

Question

我的代码似乎工作正常，只是没有打印例外： 打印（“此输入无效。”）部分。当我试图修复它时，事情变得更糟。有人能帮我吗？谢谢您！你知道吗

样本正确输出：

Calculator
Give a number: hah, NEVER
This input is invalid.
Give a number: What?
This input is invalid.
Give a number: 100
Give a number: Just kidding
This input is invalid.
Give a number: 50
(1) +
(2) -
(3) *
(4) /
(5)sin(number1/number2)
(6)cos(number1/number2)
(7)Change numbers
(8)Quit
Current numbers: 100 50
Please select something (1-6): 2
The result is: 50
(1) +
(2) -
(3) *
(4) /
(5)sin(number1/number2)
(6)cos(number1/number2)
(7)Change numbers
(8)Quit
Current numbers: 100 50
Please select something (1-6): 8
Thank you!

我的代码：

def getnumber():
    while True:
        try:
            number = input("Give a number: ")
            if number.isdigit():
                return number

        except Exception:
            print("This input is invalid.")

def main():
    import math
    print("Calculator")
    promptForNumbers = True

    while True:

        if promptForNumbers:


            number1 = int(getnumber())

            number2 = int(getnumber())

            promptForNumbers = False
        print("(1) +\n\n(2) -\n\n(3) *\n\n(4) /\n\n(5)sin(number1/number2)\n\n(6)cos(number1/number2)\n\n(7)Change numbers\n\n(8)Quit\n")
        print("Current numbers: %s %s" % (number1, number2))
        selection = int(input("Please select something (1-8): "))        


        if selection == 1:
            print("The result is: %s" % (number1 + number2))
            print("\n")
        elif selection == 2:
            print("The result is: %s" % (number1-number2))
            print("\n")
        elif selection==3:
            print("The result is: %s" % (number1*number2))
            print("\n")
        elif selection==4:
            print("The result is: %s" % (number1/number2))
            print("\n")
        elif selection==5:
            print("The result is: %s" % math.sin(number1/number2))
            print("\n")
        elif selection==6:
            print("The result is: %s" % math.cos(number1/number2))
            print("\n")
        elif selection==8:
            print("Thank you!")
            break
        elif selection==7:
            promptForNumbers = True
        else:
            print("Selection was not correct.")  
if __name__ == "__main__":
    main()

Answer 1

试试这个：

def getnumber():
    while True:
        number = raw_input("Give a number: ")

        if number.isdigit():
            return number
        else:
            print("This input is invalid.")