擅长:python、mysql、java
<p>在python2中使用<code>raw_input</code>是比较安全的,因为它总是返回一个字符串,而{<cd2>}将尝试计算给定的字符串,这很危险。在</p>
<pre><code>def askFor(prompt):
""" ask for input, continues to ask until an integer is given
"""
number = None
while True:
try:
number = int(raw_input(prompt))
break
except ValueError:
pass # or display some hint ...
print(number) # or return or what you need ...
</code></pre>