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Python3正则表示式（3）

2018-06-28 05:38:52来源：博客园阅读 ()

正则表示式对象

对象1：

案例1：

import re 
example = 'ShanDong Institute of Business and Technology'
pattern = re.compile(r'\bB\w+\b')  # 查找以B开头的单词
pattern.findall(example)
# 结果：['Business']
pattern = re.compile(r'\w+g\b')  # 查找以字母g结尾的单词
pattern.findall(example)
# 结果：['ShanDong']
pattern = re.compile(r'\b[a-zA-Z]{3}\b')  # 查找3个字母长的单词
pattern.findall(example)
# 结果：['and']
pattern.search(example)
# 结果：<_sre.SRE_Match object; span=(31, 34), match='and'>
pattern = re.compile(r'\b\w*a\w*\b') # 查找所有含字母a的单词
pattern.findall(example)
# 结果：['ShanDong', 'and']

text = 'He was carefully disguised but captured quickly by police.'
re.findall(r'\w+ly', text)  # 查找所有以字母组合ly结尾的单词
# 结果：['carefully', 'quickly']

对象2

案例2：

example = """Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
Flat is better than nested.
Sparse is better than dense.
Readability counts."""

pattern = re.compile(r'\bb\w*\b', re.I)
print(pattern.sub('*', example))
# 结果
'''
* is * than ugly.
Explicit is * than implicit.
Simple is * than complex.
Complex is * than complicated.
Flat is * than nested.
Sparse is * than dense.
Readability counts.
'''
print(pattern.sub(lambda x: x.group(0).upper(), example))
# 结果
'''
BEAUTIFUL is BETTER than ugly.
Explicit is BETTER than implicit.
Simple is BETTER than complex.
Complex is BETTER than complicated.
Flat is BETTER than nested.
Sparse is BETTER than dense.
Readability counts.
'''
print(pattern.sub('#', example, 1))
# 结果
'''
# is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
Flat is better than nested.
Sparse is better than dense.
Readability counts.
'''