python - 如何避免 ValueError 并在 python2 中仅获取整数输入？

Question

#!/usr/bin/env python

# getting user input
height = int(raw_input("height: "))

while (height < 0 or height > 23):
    height = int(raw_input("height: "))

# building the "pyramid"
spaceCount = height
hashCount = 1

for i in range(height):
    assert height != 0
    hashCount += 1
    spaceCount -= 1
    print " " * spaceCount,
    print "#" * hashCount

如果输入不是整数，代码应不断提示用户。但如何呢？

Answer 1

您需要捕获异常。

 height = 24
 while (height < 0 or height > 23):
     try:
        height = int(raw_input("heightL "))
     except ValueError:
        print "Height needs to be an integer. Try again."