示例1：$
需求：匹配163.com的邮箱地址
#coding=utf-8 import re # 正确的地址 ret = re.match("[\w]{4,20}@163\.com", "xiaoWang@163.com") ret.group() # 不正确的地址 ret = re.match("[\w]{4,20}@163\.com", "xiaoWang@163.comheihei") ret.group() # 通过$来确定末尾 ret = re.match("[\w]{4,20}@163\.com$", "xiaoWang@163.comheihei") ret.group()
运行结果：
示例2: \b
>>> re.match(r".*\bver\b", "ho ver abc").group() 'ho ver' >>> re.match(r".*\bver\b", "ho verabc").group() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'group' >>> re.match(r".*\bver\b", "hover abc").group() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'group' >>>
示例3：\B
>>> re.match(r".*\Bver\B", "hoverabc").group() 'hover' >>> re.match(r".*\Bver\B", "ho verabc").group() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'group' >>> re.match(r".*\Bver\B", "hover abc").group() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'group' >>> re.match(r".*\Bver\B", "ho ver abc").group() Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'NoneType' object has no attribute 'group'
