Simple examples of common Python regular usage

WBOY
Release: 2016-07-21 14:53:13
Original
1118 people have browsed it

下面列出Python正则表达式的几种匹配用法:

1.测试正则表达式是否匹配字符串的全部或部分

regex=ur"" #正则表达式
if re.search(regex, subject):
do_something()
else:
do_anotherthing()
Copy after login

2.测试正则表达式是否匹配整个字符串

regex=ur"\Z" #正则表达式末尾以\Z结束
if re.match(regex, subject):
    do_something()
else:
    do_anotherthing()
Copy after login

3.创建一个匹配对象,然后通过该对象获得匹配细节(Create an object with details about how the regex matches (part of) a string)

regex=ur"" #正则表达式
match = re.search(regex, subject)
if match:
    # match start: match.start()
    # match end (exclusive): atch.end()
    # matched text: match.group()
    do_something()
else:
    do_anotherthing()
Copy after login

4.获取正则表达式所匹配的子串(Get the part of a string matched by the regex)

regex=ur"" #正则表达式
match = re.search(regex, subject)
if match:
    result = match.group()
else:
    result = ""
Copy after login

5. 获取捕获组所匹配的子串(Get the part of a string matched by a capturing group)

regex=ur"" #正则表达式
match = re.search(regex, subject)
if match:
    result = match.group(1)
else:
    result = ""
Copy after login

6. 获取有名组所匹配的子串(Get the part of a string matched by a named group)

regex=ur"" #正则表达式
match = re.search(regex, subject)
if match:
result = match.group"groupname")
else:
result = ""
Copy after login

7. 将字符串中所有匹配的子串放入数组中(Get an array of all regex matches in a string)

result = re.findall(regex, subject)
Copy after login

8.遍历所有匹配的子串(Iterate over all matches in a string)

for match in re.finditer(r"<(.*&#63;)\s*.*&#63;/\1>", subject)
    # match start: match.start()
    # match end (exclusive): atch.end()
    # matched text: match.group()
Copy after login

9.通过正则表达式字符串创建一个正则表达式对象(Create an object to use the same regex for many operations)

reobj = re.compile(regex)
Copy after login

10.用法1的正则表达式对象版本(use regex object for if/else branch whether (part of) a string can be matched)

reobj = re.compile(regex)
if reobj.search(subject):
    do_something()
else:
    do_anotherthing()
Copy after login

11.用法2的正则表达式对象版本(use regex object for if/else branch whether a string can be matched entirely)

reobj = re.compile(r"\Z") #正则表达式末尾以\Z 结束
if reobj.match(subject):
    do_something()
else:
    do_anotherthing()
Copy after login

12.创建一个正则表达式对象,然后通过该对象获得匹配细节(Create an object with details about how the regex object matches (part of) a string)

reobj = re.compile(regex)
match = reobj.search(subject)
if match:
    # match start: match.start()
    # match end (exclusive): atch.end()
    # matched text: match.group()
    do_something()
else:
    do_anotherthing()
Copy after login

13.用正则表达式对象获取匹配子串(Use regex object to get the part of a string matched by the regex)

reobj = re.compile(regex)
match = reobj.search(subject)
if match:
    result = match.group()
else:
    result = ""
Copy after login

14.用正则表达式对象获取捕获组所匹配的子串(Use regex object to get the part of a string matched by a capturing group)

reobj = re.compile(regex)
match = reobj.search(subject)
if match:
    result = match.group(1)
else:
    result = ""
Copy after login

15.用正则表达式对象获取有名组所匹配的子串(Use regex object to get the part of a string matched by a named group)

reobj = re.compile(regex)
match = reobj.search(subject)
if match:
    result = match.group("groupname")
else:
    result = ""
Copy after login

16.用正则表达式对象获取所有匹配子串并放入数组(Use regex object to get an array of all regex matches in a string)

reobj = re.compile(regex)
result = reobj.findall(subject)
Copy after login

17.通过正则表达式对象遍历所有匹配子串(Use regex object to iterate over all matches in a string)

reobj = re.compile(regex)
for match in reobj.finditer(subject):
    # match start: match.start()
    # match end (exclusive): match.end()
    # matched text: match.group()
Copy after login

字符串替换

1.替换所有匹配的子串

#用newstring替换subject中所有与正则表达式regex匹配的子串
result = re.sub(regex, newstring, subject)
Copy after login

2.替换所有匹配的子串(使用正则表达式对象)

reobj = re.compile(regex)
result = reobj.sub(newstring, subject)
Copy after login

字符串拆分

1.字符串拆分

result = re.split(regex, subject)
Copy after login

2.字符串拆分(使用正则表示式对象)

reobj = re.compile(regex)
result = reobj.split(subject)
Copy after login

以上这篇常见python正则用法的简单实例就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持脚本之家。

Related labels:
source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template