Question

我正在尝试使用Automate the Boring Stuff一书中的一个小程序。

我想确保输入非int变量的人不会使程序崩溃。代码踢出一个错误，说“break”命令不在循环中。任何帮助，将不胜感激。

import random
print ('Hello. What is your name?')
name = input()
secretNumber=random.randint(1,20)
print('Well ' + name + ', I\'m thinking of a number between 1 and 20.')

for guessesTaken in range(1,7):
    print()
    print ('Take a guess')
try:
    guess = int(input())

except ValueError:
    print ('I said guess a number not letters or words.')

    if guess < secretNumber:
        print('Your guess is too low.')
    elif guess > secretNumber:
        print('Your guess is too high.')
    else:
        break

if guess == secretNumber:
    print('Good job! You guessed it.')
else:
    print('Nope the number I was thinking of was ' + str(secretNumber)+' sorry.')

Answer 1

您的缩进不正确。请注意，try块及其下方的所有内容都不再位于for循环中。

Answer 2

嗯，首先，请记住始终在此处发布您的代码，这样您就可以避免掉线。

在查看代码时，我可以轻松地告诉您一些事情：

1）缩进这段代码，因为它实际上超出了for循环。

try:
    guess = int(input())

except (ValueError, NameError):
    print ('I said guess a number not letters or words.')
    break

if guess < secretNumber:
    print('Your guess is too low.')
elif guess > secretNumber:
    print('Your guess is too high.')
else:
    break

2）你应该在except块中休息（就像我上面所做的那样），这样它就不会执行下一个if语句块，或者你也会得到{NameError语句的例外1}}因为未创建guess变量，下一个if语句if guess "<" secretNumber:会抛出异常。

3）这段代码有点破碎，因为如果它抛出异常并且没有创建猜测，if循环中的最后for语句也会抛出异常，所以我建议你在for语句之前初始化该变量，如下所示：guess = 0。

您的最终代码应如下所示：

import random
print ('Hello. What is your name?')
name = input()
secretNumber=random.randint(1,20)
print('Well ' + name + ', I\'m thinking of a number between 1 and 20.')
guess = 0

for guessesTaken in range(1,7):
    print()
    print ('Take a guess')
    try:
        guess = int(input())

    except (ValueError, NameError):
        print ('I said guess a number not letters or words.')
        break

    if guess < secretNumber:
        print('Your guess is too low.')
    elif guess > secretNumber:
        print('Your guess is too high.')
    else:
        break

if guess == secretNumber:
    print('Good job! You guessed it.')
elif guess == 0:
    None
else:
    print('Nope the number I was thinking of was ' + str(secretNumber)+' sorry.')

仍有改进的余地，但这将满足您的要求。

度过美好的一天=）。

Python尝试/除外

2 个答案: