擅长:python、mysql、java
<p>处理这个问题的python方法叫做<a href="https://docs.python.org/3/glossary.html#term-eafp" rel="nofollow noreferrer">EAFP</a>:请求原谅比允许更容易。用<code>try</code>和<code>except</code>语句包装代码,以便在输入无效内容时进行检测</p>
<pre><code>try:
user_choice = int(input("""
(1)Paper, (2)Scissors, (3)Rock!: """))
except ValueError:
# do something here like display an error message and set a flag to loop for input again
</code></pre>
<p>如果这不适合您的风格,那么在执行此操作之前,很容易检查字符串以确保它可以转换为整数:</p>
<pre><code>bad_input = True
while bad_input:
user_choice = input("""
(1)Paper, (2)Scissors, (3)Rock!: """)
if user_choice.isnumeric():
user_choice = int(user_choice)
if user_choice in (1, 2, 3):
bad_input = False
else:
print("Bad input, try again.")
</code></pre>