python-3.x - 如何处理ValueError？

Question

因此，这是一个小猜谜游戏，您有9次尝试猜测0到100之间的数字。但是，如果用户输入字符串值，则会得到ValueError。如何处理ValueError？

for Guesses in range(9):
        print('Take a guess.')

        Guess = int(input())

        if Guess < 0:
            print('Please enter a positive number')
        elif Guess > 100:
            print('The number is only between 0 and 100')
        elif Guess < Number:
            print('Higher...')
        elif Guess > Number:
            print('Lower...')           
        else:
            print('Spot on!')
            break # Guess was correct

Answer 1

使用try和except。尝试这个:

for Guesses in range(9):
        print('Take a guess.')
        while True:
            try:
                Guess = int(input())
                break
            except ValueError:
                print("Try again. That is not a number")

        if Guess < 0:
            print('Please enter a positive number')
        elif Guess > 100:
            print('The number is only between 0 and 100')
        elif Guess < Number:
            print('Higher...')
        elif Guess > Number:
            print('Lower...')           
        else:
            print('Spot on!')
            break # Guess was correct

一些进步:

for Guesses in range(9):
        print('Take a guess.')
        while True:
            try:
                Guess = int(input())
                if (0 > Guess):
                    print('Please enter a positive number')
                elif (100 < Guess):
                    print('The number is only between 0 and 100')
                else:
                    break
            except ValueError:
                print("Try again. That is not a number")
        elif Guess < Number:
            print('Higher...')
        elif Guess > Number:
            print('Lower...')           
        else:
            print('Spot on!')
            break # Guess was correct

另外，建议变量名不要大写。