#!/usr/bin/python
# -*- coding: UTF-8 -*-
import string
s = raw_input('请输入一个字符串:n')
letters = 0
space = 0
digit = 0
others = 0
i=0
while i < len(s):
c = s[i]
i += 1
if c.isalpha():
letters += 1
elif c.isspace():
space += 1
elif c.isdigit():
digit += 1
else:
others += 1
print 'char = %d,space = %d,digit = %d,others = %d' % (letters,space,digit,others)
实例（Python3.x） - 使用 for 循环#!/usr/bin/python3
import string
s = input('请输入一个字符串:n')
letters = 0
space = 0
digit = 0
others = 0
for c in s:
if c.isalpha():
letters += 1
elif c.isspace():
space += 1
elif c.isdigit():
digit += 1
else:
others += 1
print ('char = %d,space = %d,digit = %d,others = %d' % (letters,space,digit,others))
以上实例输出结果为：
请输入一个字符串:
123runoobc kdf235*(dfl
char = 13,space = 2,digit = 6,others = 2
