请教一个 re 正则的问题

推荐学习书目

› Learn Python the Hard Way

Python Sites

› PyPI - Python Package Index

› http://diveintopython.org/toc/index.html

› Pocoo

值得关注的项目

› PyPy

› Celery

› Jinja2

› Read the Docs

› gevent

› pyenv

› virtualenv

› Stackless Python

› Beautiful Soup

› 结巴中文分词

› Green Unicorn

› Sentry

› Shovel

› Pyflakes

› pytest

Python 编程

› pep8 Checker

Styles

› PEP 8

› Google Python Style Guide

› Code Style from The Hitchhiker's Guide

This topic created in 2007 days ago, the information mentioned may be changed or developed.

匹配数字三连....

import re

s = 'abc 456 def'

re.search('\d\d\d', s)       # 成功
re.search('\d{3}', s)        # None
re.search('[0-9]{3}', s)    # 成功

为什么 \d{3} 不行, 我在在线正则测试的工具网站上试过 \d{3} 并没有错, google 也没找到有说明的, 可能是关键字不对

Arch

正则

def'

import

9 replies • 2021-05-10 09:24:46 +08:00

oldshensheep

May 9, 2021

https://imgur.com/zwXJpap
?

Trim21

May 9, 2021 via Android

试了试第二个能正确匹配

cherbim

May 9, 2021 via iPhone

我测试第二个成功啊

ClericPy

May 9, 2021

python 3.7 3.8 3.9 2.7 都能正确匹配

要不你试试 r'\d{3}'

iptables

May 9, 2021

我的测试结果

$ python3.9
Python 3.9.5 (default, May 3 2021, 19:12:05)
[Clang 12.0.5 (clang-1205.0.22.9)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
>>> import re
>>>
>>> s = 'abc 456 def'
>>>
>>> re.search('\d\d\d', s)
<re.Match object; span=(4, 7), match='456'>
>>> re.search('\d{3}', s)
<re.Match object; span=(4, 7), match='456'>
>>> re.search('[0-9]{3}', s)
<re.Match object; span=(4, 7), match='456'>
>>>
>>> re.search(r'\d\d\d', s)
<re.Match object; span=(4, 7), match='456'>
>>> re.search(r'\d{3}', s)
<re.Match object; span=(4, 7), match='456'>
>>> re.search(r'[0-9]{3}', s)
<re.Match object; span=(4, 7), match='456'>
>>>