Python中正则表达式的用法实例汇总
作者:shichen2014 时间:2021-10-02 07:48:08
正则表达式是Python程序设计中非常实用的功能,本文就常用的正则表达式做一汇总,供大家参考之用。具体如下:
一、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, number = re.subn(regex, newstring, subject)
2.替换所有匹配的子串(使用正则表达式对象)
reobj = re.compile(regex)
result, number = reobj.subn(newstring, subject)
二、字符串拆分
1.字符串拆分
result = re.split(regex, subject)
2.字符串拆分(使用正则表示式对象)
reobj = re.compile(regex)
result = reobj.split(subject)
三、匹配
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()
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()
3. 创建一个匹配对象,然后通过该对象获得匹配细节
regex=ur"..." #正则表达式
match = re.search(regex, subject)
if match:
# match start: match.start()
# match end (exclusive): match.end()
# matched text: match.group()
do_something()
else:
do_anotherthing()
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 = ""
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 = ""
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 = ""
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)
8.遍历所有匹配的子串
(Iterate over all matches in a string)
for match in re.finditer(r"<(.*?)\s*.*?/\1>", subject)
# match start: match.start()
# match end (exclusive): match.end()
# matched text: match.group()
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)
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()
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()
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): match.end()
# matched text: match.group()
do_something()
else:
do_anotherthing()
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 = ""
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 = ""
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 = ""
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)
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()
感兴趣的读者可以动手调试一下本文实例代码,相信会有新的收获。
标签:Python,正则表达式,用法
![](/images/zang.png)
![](/images/jiucuo.png)
猜你喜欢
各种SQL语句速查手册
2007-09-27 19:31:00
python实现简单http服务器功能
2023-03-24 15:36:58
![](https://img.aspxhome.com/file/2023/9/120949_0s.jpg)
Python数据结构之队列详解
2023-11-17 14:04:34
![](https://img.aspxhome.com/file/2023/5/76795_0s.png)
python import 引用上上上级包的三种方法
2021-09-22 12:56:38
Python logging日志库空间不足问题解决
2021-08-24 15:59:17
![](https://img.aspxhome.com/file/2023/8/105348_0s.png)
ASP分页技术详解
2007-08-13 15:25:00
![](https://img.aspxhome.com/file/UploadPic/20078/13/2007813153154844s.jpg)
Python如何读取、写入JSON数据
2021-10-26 18:28:19
PHP面向对象程序设计高级特性详解(接口,继承,抽象类,析构,克隆等)
2023-11-23 11:35:00
Google的产品设计指导思想
2008-03-23 14:15:00
![](https://img.aspxhome.com/file/UploadPic/20083/23/2008323141844207s.jpg)
Python pygame绘制文字制作滚动文字过程解析
2022-06-10 13:21:11
Python多线程的使用详情
2023-05-29 15:13:36
python中opencv图像叠加、图像融合、按位操作的具体实现
2023-11-11 21:39:21
![](https://img.aspxhome.com/file/2023/4/71524_0s.png)
python的pip安装以及使用教程
2022-12-05 11:04:37
![](https://img.aspxhome.com/file/2023/9/72919_0s.png)
Oracle批量查询、删除、更新使用BULK COLLECT提高效率
2023-07-14 03:15:52
Python自然语言处理 NLTK 库用法入门教程【经典】
2022-10-06 04:36:54
django中使用Celery 布式任务队列过程详解
2022-07-08 02:25:55
![](https://img.aspxhome.com/file/2023/9/112139_0s.png)
pytorch加载预训练模型与自己模型不匹配的解决方案
2023-06-17 14:22:24
python实现人性化显示金额数字实例详解
2023-11-04 12:40:10
网站开发防止中文乱码需要了解的codepage的重要性小结
2011-03-03 11:24:00
十分钟利用Python制作属于你自己的个性logo
2021-08-25 05:12:41
![](https://img.aspxhome.com/file/2023/2/80762_0s.jpg)