Python检查整数输入 [英] Python check for integer input
本文介绍了Python检查整数输入的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我试图允许用户输入我的程序,但是当他们输入字符串时,我的程序失败.到目前为止,这是一个更大的程序,但正在尝试纠正该问题:
I am trying to allow a user to input into my program, however when they enter a string my program fails. It is for a bigger program but was trying to correct the problem, I have so far:
data = raw_input('Enter a number: ')
number = eval(data)
if type(number) != int:
print"I am afraid",number,"is not a number"
elif type(number) == int:
if data > 0:
print "The",number,"is a good number"
else:
print "Please enter a positive integer"
当用户输入字符串时,它返回:
when the user enters a string, it returns:
number = eval(data)
File "<string>", line 1, in <module>
NameError: name 'hel' is not defined
任何帮助将不胜感激.
推荐答案
您正在使用eval
,它将评估在当前上下文中作为Python表达式传递的字符串.您只想做
You're using eval
, which evaluate the string passed as a Python expression in the current context. What you want to do is just
data = raw_input('Enter a number: ')
try:
number = int(data)
except ValueError:
print "I am afraid %s is not a number" % data
else:
if number > 0:
print "%s is a good number" % number
else:
print "Please enter a positive integer"
这将尝试将输入解析为整数,如果输入失败,则显示错误消息.
This will try to parse the input as an integer, and if it fails, displays the error message.
这篇关于Python检查整数输入的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文