re.match与re.search的区别

re.match只匹配字符串的开始，如果字符串开始不符合正则表达式，则匹配失败，函数返回None；而re.search匹配整个字符串，直到找到一个匹配。

import re
 
line = "Cats are smarter than dogs";
 
matchObj = re.match( r'dogs', line, re.M|re.I)
if matchObj:
   print "match --> matchObj.group() : ", matchObj.group()
else:
   print "No match!!"
 
matchObj = re.search( r'dogs', line, re.M|re.I)
if matchObj:
   print "search --> searchObj.group() : ", matchObj.group()
else:
   print "No match!!"