Python Text Processing 简明教程
Python - Search and Match
在使用正则表达式时,有两个基本操作看似相似,但存在重大差异。 re.match() 仅检查字符串开头的匹配项,而 re.search() 检查字符串中的任意位置的匹配项。这在文本处理中起着重要的作用,因为我们经常必须编写正确的正则表达式来检索文本块,例如进行情感分析。
import re
if re.search("tor", "Tutorial"):
print "1. search result found anywhere in the string"
if re.match("Tut", "Tutorial"):
print "2. Match with beginning of string"
if not re.match("tor", "Tutorial"):
print "3. No match with match if not beginning"
# Search as Match
if not re.search("^tor", "Tutorial"):
print "4. search as match"
当我们运行以上程序时,我们得到以下输出:
1. search result found anywhere in the string
2. Match with beginning of string
3. No match with match if not beginning
4. search as match