高级特性-正则表达式

re.search(pattern,string,flag)

与re.match()不同，匹配整个字符串，match如果开始不匹配则返回none

2. re.sub替换

re.sub(pattern,replace,string)

#!/bin/python

import re

#re.sub function testing

phone="Cats are smarter than dogs"

number=re.sub('\D',"",phone)

print(number)

#re.searach function testing
#caution: space in the regex
matchObj=re.search("(.*) are (.*?) .*",phone,re.M|re.I)
if matchObj:
print(matchObj.groups())