正则表达式的经典实例

本文给大家总结了16种python正则表达式使用经典实例，非常不错具有参考借鉴价值，感兴趣的朋友一起学习吧！

下面列出Python正则表达式的几种匹配用法，具体内容如下所示：

1.测试正则表达式是否匹配字符串的全部或部分

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

实例：

regex='1[3458]\\d{9}' #正则表达式
subject='13000000002'
if re.search(regex, subject):
    print 'right'
else:
    print 'error'

2.测试正则表达式是否匹配整个字符串

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

实例：

'''手机号正则表达式'''
regex='1[3458]\\d{9}\Z' #正则表达式
subject='13000000001'
if re.match(regex, subject):
    print 'right'
else:
    print 'error'

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:
    do_something()
else:
    do_anotherthing()

实例：

regex='1[3458]\\d{9}' #正则表达式
subject='13000000002'
match=re.search(regex, subject)
if match:
    print 'right'
else:
    print 'error'

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 = ""

实例：

regex='1[3458]\\d{9}\Z' #正则表达式
subject='13000000002'
match=re.search(regex, subject)
if match:
    result=match.group()
    print result
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 = ""

实例：

regex='1[3458]\\d{9}\Z' #正则表达式
subject='13000000002'
match=re.search(regex, subject)
if match:
    result=match.group(0)
    print result
else:
    result=''
    print 'error'

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)

实例：

regex='1[3458]\\d{9}\Z' #正则表达式
subject='13000000002'
result = re.findall(regex, subject)
print result

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)

实例：

regex='1[3458]\\d{9}\Z' #正则表达式
subject='13000000002'
for match in re.finditer(regex, subject):
    print 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)

实例：

import re
#将正则表达式编译成pattern对象
pattern=re.compile('hello')

#使用pattern匹配文本，获得匹配结果，无法匹配时将返回None
match=pattern.match('hello world!')
if match:
    print match.group()
else:
    print u"无法匹配"

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()

实例：

pattern=re.compile('hello')

#使用pattern匹配文本，获得匹配结果，无法匹配时将返回None
if pattern.search('hello world!'):

    print 'right'
else:
    print u"无法匹配"

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): atch.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)