一，正则表达式

　　正则表达式是对字符串操作的一种逻辑公式，我们一般使用正则表达式对字符串进行匹配和过滤，使用正则的优缺点，我们可以去http://tool.chinaz.com/regex/进行测试。

　　优点：灵活，功能性强，逻辑性强

　　缺点：上手难，一旦上手，使用起来很方便

　　正则表达式由普通字符和元字符组成，普通字符包含大小写字母，数字，在匹配普通字符的时候我们直接写就好，比如‘abc’匹配的就是‘abc’。元字符才是正则表达式的灵魂。

　　1，字符组：字符组很简单，用[]括起来，在[]中出现的内容会被匹配，例如[abc]匹配a或b或c，如果字符组中的内容过多还可以使用-，例如[a-z]匹配a到z之间的所有字母，[0-9]匹配所有阿拉伯数字

　　2，简单元字符

　　

　　

　　3，量词

　　

　　4，惰性匹配和贪婪匹配

　　

　　

　　5，分组

　　

　　6，转义

　　

二，re模块

　　

　　

　　

　　

　　

三，实例一，用re和urllib爬电影下载地址，我爬的是电影天堂小片网的电影（中间一大段if，elif只是排除编码有问题电影）　

from urllib.request import urlopen
import re
for i in range(1,302):
    if i ==1:
        url='https://www.dy2018.com/html/gndy/dyzz/index.html'
    else:
        url='https://www.dy2018.com/html/gndy/dyzz/index_%s.html'%i
    print(url)
    f1 = open('move.txt', mode='a', encoding='utf-8')
    f1.write(url + '\n')
    f1.close()
    content=urlopen(url).read().decode('gbk')
    if i==51:
        obj = re.compile(r'<td height="20" style="padding-left:3px">&nbsp;</td>.*?<td height="26">.*?a href="/(?P<adress>.*?)".*?">(?P<name>.*?)</a>', re.S)
    else:
        obj = re.compile(r'<td height="26">.*?a href="/(?P<adress>.*?)".*?">(?P<name>.*?)</', re.S)
    ss=obj.finditer(content)
    for el in ss:
        if el.group('adress')=='i/91900.html' or el.group('adress')=='html/gndy/dyzz/20130913/91826.html' :
            continue
        elif el.group('adress')=='html/gndy/dyzz/20130131/41375.html'or el.group('adress')=='html/gndy/dyzz/20130903/91759.html':
            continue
        elif el.group('adress')=='html/gndy/dyzz/20130908/91797.html'or el.group('adress')=='html/gndy/dyzz/20120623/38354.html':
            continue
        elif el.group('adress')=='html/gndy/dyzz/20110219/30940.html'or el.group('adress')=='html/gndy/dyzz/20110112/30354.html':
            continue
        elif el.group('adress')=='html/gndy/dyzz/20110109/30300.html'or el.group('adress')=='html/gndy/dyzz/20110107/30267.html':
            continue
        elif el.group('adress')=='html/gndy/dyzz/20101231/30152.html'or el.group('adress')=='html/gndy/dyzz/20101231/30150.html':
            continue
        elif el.group('adress')=='html/gndy/dyzz/20101221/29988.html'or el.group('adress')=='html/gndy/dyzz/20101215/29886.html':
            continue
        elif el.group('adress')=='html/gndy/dyzz/20101209/29780.html'or el.group('adress')=='html/gndy/dyzz/20101208/29768.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20101101/29127.html'or el.group('adress') == 'html/gndy/dyzz/20101027/29031.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20101019/28883.html'or el.group('adress') == 'html/gndy/dyzz/20100919/28321.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20100909/28122.html'or el.group('adress') == 'html/gndy/dyzz/20100828/27899.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20100820/27742.html'or el.group('adress') == 'html/gndy/dyzz/20100726/27308.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20100620/26683.html'or el.group('adress') == 'html/gndy/dyzz/20100613/26564.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20100428/25809.html'or el.group('adress') == 'html/gndy/dyzz/20100116/24050.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20100110/23933.html'or el.group('adress') == 'html/gndy/dyzz/20100103/23790.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20091104/22691.html'or el.group('adress') == 'html/gndy/dyzz/20090423/18292.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20090308/17370.html'or el.group('adress') == 'html/gndy/dyzz/20090303/17285.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20090308/17377.html'or el.group('adress') == 'html/gndy/dyzz/20090113/16496.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20081221/16079.html'or el.group('adress') == 'html/gndy/dyzz/20081215/15964.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20081008/14637.html'or el.group('adress') == 'html/gndy/dyzz/20080916/14200.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20080905/13985.html'or el.group('adress') == 'html/gndy/dyzz/20080119/9339.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20071213/8253.html'or el.group('adress') == 'html/gndy/dyzz/20071125/7635.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20071025/6879.html'or el.group('adress') == 'html/gndy/dyzz/20070902/5424.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070824/5143.html'or el.group('adress') == 'html/gndy/dyzz/20070823/5109.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070823/5088.html'or el.group('adress') == 'html/gndy/dyzz/20070806/4621.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070805/4617.html'or el.group('adress') == 'html/gndy/dyzz/20070805/4611.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070727/4333.html'or el.group('adress') == 'html/gndy/dyzz/20070726/4301.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070716/4023.html'or el.group('adress') == 'html/gndy/dyzz/20070712/3862.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070617/3072.html'or el.group('adress') == 'html/gndy/dyzz/20070615/3019.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070527/2418.html'or el.group('adress') == 'html/gndy/dyzz/20070425/1672.html':
            continue
        elif el.group('adress') == 'html/gndy/dyzz/20070416/1478.html'or el.group('adress') == 'html/gndy/dyzz/20070412/1399.html':
            continue
        d1={}
        d1['name']=el.group('name')
        url1='https://www.dy2018.com/'+el.group('adress')
        content1 = urlopen(url1).read().decode('gbk')
        obj1=re.compile(r'下载地址.*?<a href="(?P<adress1>.*?)">',re.S)
        ss1=obj1.search(content1)
        d1['adress']=ss1.group('adress1')
        f1=open('move.txt',mode='a',encoding='utf-8')
        f1.write(str(d1)+'\n')
        f1.close()
四，用re和urllib爬维密图片
import re
from urllib.request import urlopen,urlretrieve
for n in range(1,5):
    if n ==1:
        url2 = 'https://stock.tuchong.com/topic?topicId=49282'
    else:
        url2='https://stock.tuchong.com/topic?topicId=49282&page=%s&count=100'%n
    content=urlopen(url2).read().decode('utf-8')
    obj=re.compile(r'"imageId":"(?P<bianhao>.*?)"',re.S)
    ss=obj.finditer(content)
    i=(n-1)*100+1
    for el in ss:
        num=el.group('bianhao')
        if num=='525558981780570122'or num=='525569719200382978':
            continue
        elif num=='525589673617915918'or num=='525563551629443081':
            continue
        elif num == '525571411419332618'or num == '525585163906711562':
            continue
        elif num == '525554334627135503'or num == '525554274497593347':
            continue
        elif num == '525555872228048910'or num == '525555889405689865':
            continue
        elif num == '525566472207728651'or num == '525569650482741255':
            continue
        elif num == '525571420010053640'or num == '525571196669132802':
            continue
        elif num == '525571239618281484'or num == '525575964084666381':
            continue
        elif num == '525577347064528914'or num == '525580594059804675':
            continue
        elif num == '525592946387451916'or num == '525602292234190873':
            continue
        elif num == '525551036092645412'or num == '525552685360087057':
            continue
        elif num == '525554300266217477'or num == '525555657477062662':
            continue
        elif num == '525557349694570506'or num == '525557418413522955':
            continue
        elif num == '525575757924401164'or num == '525585146722910211':
            continue
        elif num == '525591194036862980'or num == '525594604244828160':
            continue
        elif num == '525619248767172615'or num == '525546397526392859':
            continue
        elif num == '525547952305733639'or num == '525549618751864836':
            continue
        elif num == '525552539333034011'or num == '525560631049584650':
            continue
        elif num == '525561910952460294'or num == '525577252573020167':
            continue
        elif num == '525577390015905802'or num == '525578919019806730':
            continue
        elif num == '525589845421064206'or num == '525600746043736066':
            continue
        elif num == '525600746046750729'or num == '525600539888320533':
            continue
        elif num == '525636059267465227'or num == '525551070454611970':
            continue
        elif num == '525551173533827166'or num == '525552693952643113':
            continue
        elif num == '525557461366341633'or num == '525557169308041219':
            continue
        elif num == '525558818575613969'or num == '525559024730243078':
            continue
        elif num == '525560596692074509'or num == '525563345468391437':
            continue
        elif num == '525575809462435842'or num == '525578901843083269':
            continue
        elif num == '525580405077442575'or num == '525582148835344441':
            continue
        elif num == '525585146721337349'or  num == '525549532855926790':
            continue
        elif num == '525552711133822979'or  num == '525560338990235661':
            continue
        elif num == '525565097818193935'or num == '525566489386811399':
            continue
        elif num == '525569684840644622'or num == '525571239620640780':
            continue
        elif num == '525571316927692806'or num == '525572725675917316':
            continue
        elif num == '525573017733693460'or num == '525574254687682562':
            continue
        elif num == '525574538153689102'or num == '525575869593550849':
            continue
        elif num == '525594295007182858'or num == '525596004400234497':
            continue
        elif num == '525608305186177028'or num == '525650120992096265':
            continue
        elif num == '525564900245504013':
            continue
        s='http://p3.pstatp.com/weili/ms/%s.webp'%num
        print(s)
        ss=urlretrieve(s,'维密\%s.jpg'%i)
        i += 1
												


											
正则表达式，re模块的更多相关文章
	

    
						
  1. python正则表达式Re模块备忘录
		
    title: python正则表达式Re模块备忘录 date: 2019/1/31 18:17:08 toc: true --- python正则表达式Re模块备忘录 备忘录 python中的数量词为 ...
    
		
    2. 
						
  2. python 正则表达式re模块
		
    #####################总结##############    优点:  灵活, 功能性强, 逻辑性强.               缺点:  上手难,旦上手, 会爱上这个东西    ...
    
		
    3. 
						
  3. python基础之正则表达式 re模块
		
    内容梗概: 1. 正则表达式 2. re模块的使⽤ 3. 一堆练习正则表达式是对字符串串操作的一种逻辑公式. 我们一般使用正则表达式对字符串进行匹配和过滤.使用正则的优缺点: 优点: 灵活,功能性强, ...
    
		
    4. 
						
  4. python记录_day23 正则表达式  re模块
		
    一. 正则表达式 使用python的re模块之前应该对正则表达式有一定的了解 正则表达式是对字符串操作的一种逻辑公式.我们一般使用正则表达式对字符串进行匹配和过滤. 正则的优缺点: 优点:灵活, 功能 ...
    
		
    5. 
						
  5. Python面试题之Python正则表达式re模块
		
    一.Python正则表达式re模块简介 正则表达式,是一门相对通用的语言.简单说就是:用一系列的规则语法,去匹配,查找,替换等操作字符串,以达到对应的目的:此套规则,就是所谓的正则表达式.各个语言都有 ...
    
		
    6. 
						
  6. Python 正则表达式——re模块介绍
		
    Python 正则表达式 re 模块使 Python 语言拥有全部的正则表达式功能,re模块常用方法: re.match函数 re.match从字符串的起始位置匹配,如果起始位置匹配不成功,则matc ...
    
		
    7. 
						
  7. 学习django之正则表达式re模块
		
    re(regular expression)模块 正则表达式(regular expression)主要功能是从字符串(string)中通过特定的模式(pattern),搜索想要找到的内容. 一.re ...
    
		
    8. 
						
  8. 正则表达式re模块
		
    正则表达式模块re 1. 正则简介 就其本质而言,正则表达式(或 RE)是一种小型的.高度专业化的编程语言, (在Python中)它内嵌在Python中,并通过 re 模块实现.正则表达式模式被 编译 ...
    
		
    9. 
						
  9. python正则表达式——re模块
		
    http://blog.csdn.net/zm2714/article/details/8016323 re模块 开始使用re Python通过re模块提供对正则表达式的支持.使用re的一般步骤是先将 ...
    
		
    10. 
						
  10. Python自动化运维之8、正则表达式re模块
		
    re模块 正则表达式使用单个字符串来描述.匹配一系列符合某个句法规则的字符串,在文本处理方面功能非常强大,也经常用作爬虫,来爬取特定内容,Python本身不支持正则,但是通过导入re模块,Python ...
    
		
    11. 
		

	


随机推荐
	

    
									
  1. Hbase 性能改进
			
    第一种性能改进方式:
    
			
    2. 
						
  2. Alpha项目冲刺
			
    一.团队成员 学号 姓名 211606361 何承华(队长) 211606356 陈宇 211606360 丁培辉 211606333 温志铭 211606343 杨宇潇 211606391 张主强  ...
    
			
    3. 
						
  3. C语言基础课第五次作业
			
    PTA第五次作业 7-2 统计一行文本中的单词个数 一.程序代码 #include<stdio.h> int main(void) { ]; ,word=; char c; gets(st ...
    
			
    4. 
						
  4. Codeforces Round #486 (Div. 3) D. Points and Powers of Two
			
    Codeforces Round #486 (Div. 3) D. Points and Powers of Two 题目连接: http://codeforces.com/group/T0ITBvo ...
    
			
    5. 
						
  5. 初识RabbitMQ
			
    1.安装 rabbitmq官网:http://www.rabbitmq.com/ 下载地址:https://packagecloud.io/rabbitmq 下载rabbitmq-server 安装脚 ...
    
			
    6. 
						
  6. unique(未完成)
			
    const unique = arr => { const sortedArr = arr.sort((a, b) => a > b); const first = sortedAr ...
    
			
    7. 
						
  7. 初识The ONE
			
    Author:bakari  Date:2014.1.14 转载请注出处:http://www.cnblogs.com/bakari/p/3519841.html,谢谢! 本学期开始做真正意义上的研究 ...
    
			
    8. 
						
  8. HoloLens开发手记 - 使用Visual Studio Using Visual Studio
			
    不论你是否使用DirectX或Unity来开发全息应用,你都会使用Visual Studio 2015来进行调试和部署应用.在本部分,你将会学习以下内容: 如何通过Visual Studio将你的应用 ...
    
			
    9. 
						
  9. 微服务开发有道之把项目迁移到Kubernetes上的5个小技巧
			
    我们将在本文中提供5个诀窍帮你将项目迁移到Kubernetes上,这些诀窍来源于过去12个月中OpenFaas社区的经验.下文的内容与Kubernetes 1.8兼容,并且已经应用于OpenFaaS  ...
    
			
    10. 
						
  10. Apache多站点配置（ubuntu）（原创）
			
      1,先进入Apaches2的目录下 cd /etc/apache2   2,进入sites-available中 cd sites-available vi 000-default.conf    ...
    
			
    11.