python - 值错误 : invalid literal for int() with base 10: 'stop'

Question

每次我尝试编写代码时，它都能正常工作，但当我输入 'stop' 时，它会给我一个错误:

ValueError: invalid literal for int() with base 10: 'stop'

def guessingGame():
    global randomNum
    guessTry = 3

    while True:
        guess = input('Guess a Number between 1 - 10, You have 3 Tries, or Enter Stop:  ')
        if int(guess) == randomNum:
            print('Correct')
            break

        if int(guess) < randomNum:
            print('Too Low')
            guessTry = guessTry - 1
            print('You have, ' + str(guessTry) + ' Guesses Left')

        if int(guess) > randomNum:
            print('Too High')
            guessTry = guessTry - 1
            print('You have, ' + str(guessTry) + ' Guesses Left')

        if guessTry == 0:
            print('You have no more tries')
            return

        if str(guess) == 'stop' or str(guess) == 'Stop':
            break

Answer 1

传递给 int() 的字符串应该只包含数字:

>>> int("stop")
Traceback (most recent call last):
  File "<ipython-input-114-e5503af2dc1c>", line 1, in <module>
    int("stop")
ValueError: invalid literal for int() with base 10: 'stop'

快速解决方法是使用 exception handling这里:

def guessingGame():
    global randomNum
    global userScore
    guessTry = 3

    while True:
        guess = input('Guess a Number between 1 - 10, You have 3 Tries, or Enter Stop:  ')
        try:
            if int(guess) == randomNum:
                print('Correct')
                break

            if int(guess) < randomNum:
               print('Too Low')
               guessTry = guessTry - 1
               print('You have, ' + str(guessTry) + ' Guesses Left')

            if int(guess) > randomNum:
                print('Too High')
                guessTry = guessTry - 1
                print('You have, ' + str(guessTry) + ' Guesses Left')

            if guessTry == 0:
                print('You have no more tries')
                return
        except ValueError:
            #no need of str() here
            if guess.lower() == 'stop':
                break
guessingGame()

并且您可以使用 guess.lower() == 'stop' 来匹配“stop”的任何大小写组合:

>>> "Stop".lower() == "stop"
True
>>> "SToP".lower() == "stop"
True
>>> "sTOp".lower() == "stop"
True