python的re（正则表达式）

python re

import re
s = '''bottle\nbag\nbig\napple'''
for i,c in enumerate(s, 1):
    print((i-1, c), end="\n" if i%8==0 else ' ')
    
print()

print('--match--')
result = re.match('b', s) 
print(1, result) 
result = re.match('a', s) 
print(2, result)
result = re.match('^a', s, re.M)
print(3, result)
result = re.match('^a', s, re.S) 
print(4, result)
# 先编译，然后使用正则表达式对象
regex = re.compile('a')
result = regex.match(s) 
print(5, result)
result = regex.match(s, 15) 
print (6, result) #
print('--search--')
result = re.search('a', s)
print(7, result)
regex = re.compile('a')
result =regex.search(s, 15)
print(8, result)
regex = re.compile('^b')
result =regex.search(s,11)
print(9, result)
result = re.fullmatch ('bag', s)
print (10, result)
regex = re.compile ('bag')
result = regex.fullmatch(s)
print (11, result)
result = regex. fullmatch(s, 7)
print (12, result)
result = regex. fullmatch(s, 7, 10)
print(13, result) # [7, 10)

import re
s = '''bottle\nbag\nbig\nable'''
for i,c in enumerate(s, 1):
    print((i-1, c), end='\n' if i%8==0 else ' ')
print()

result = re.findall('b', s)
print(1, result)
regex = re.compile('^b')
result = regex.findall(s)
print(2, result)
regex = re.compile('^b', re.M)
result = regex.findall(s, 7)
print(3, result)
regex = re.compile('^b', re.S)
result = regex.findall(s)
print(4, result)
regex = re.compile('^b', re.S)
result = regex.findall(s, 7)
print(5, result)
regex = re.compile('^b', re.M)
result = regex.findall(s, 7, 10)
print(6, result)

import re
s = '''bottle\nbag\nbig\nable'''
for i,c in enumerate(s, 1):
    print((i-1, c), end='\n' if i%8==0 else ' ')
print()
regex = re.compile('b\wg')
result = regex.sub('magedu', s)
print(1, result)
result = regex.sub('magedu', s, 1)
print(2, result)
regex = re.compile('\s+')
result = regex.subn('\t', s)
print(6, result)

import re
s = '''01 bottle
02 bag
03    big
100     able'''
for i,c in enumerate(s, 1):
    print((i-1, c), end='\n' if i%8==0 else ' ')
print()

print(s.split())
result = re.split('[\s\d]+', s)
print(1, result)
regex = re.compile('^[\s\d]+')
result = regex.split(s)
print(2, result)
regex = re.compile('^[\s\d]+', re.M)
result = regex.split(s)
print(3, result)
regex = re.compile('\s+\d+\s+')
result = regex.split(' '+s)
print(4, result)
regex = re.compile('\s?\d{2}\d?\s+')
result = regex.split(s)
result = list(filter(None,result))
print(5, result)

import re
s = '''bottle\nbag\nbig\nable'''
for i,c in enumerate(s, 1):
    print((i-1, c), end='\n' if i%8==0 else ' ')
print()

regex = re.compile('(b\w+)')
result = regex.match(s)
print(result)
print(type(result))
print(1, 'match', result.groups())
result = regex.search(s)
print(2, 'search', result.groups())
regex = re.compile('(b\w+)\n(?P<name2>b\w+)\n(?P<name3>b\w+)')
result = regex.match(s)
print (3, 'match', result)
print(4, result.group(3), result.group(2), result.group(1))
print (5, result.group(0).encode()) 
print (6, result.group('name2'), result.group('name3'))
print (6, result.groups())
print(7, result.groupdict())
# result = regex.findall(s)
# for x in result:
#     print(type(x), x)
regex = re.compile('(?P<head>b\w+)')
result = regex.finditer(s)
for x in result:
    print(type(x), x, x.group(), x.group('head'))

原文地址：https://www.cnblogs.com/soymilk2019/p/15012275.html