使用正则表达式

Posted 2020-10-30 黄施策

学会使用正则表达式

import requestsimport re
newsurl = \'http://news.gzcc.cn/html/xiaoyuanxinwen/\'
res = requests.get(newsurl)  
res.encoding = \'utf-8\'
from bs4 import BeautifulSoup
soup = BeautifulSoup(res.text, \'html.parser\')

1. 用正则表达式判定邮箱是否输入正确。

email =  input("请输入邮箱:")
result = re.match(\'^(\\w)+(\\.\\w+)*@(\\w)+((\\.\\w{2,3}){1,3})$\',email)
if(result != None):
    print("正确")
else:
    print("错误")

2. 用正则表达式识别出全部电话号码。

import re
str = \'\'\'版权所有：广州商学院 地址：广州市黄埔区九龙大道206号
     学校办公室：020-82876130 招生电话：[phone]
     粤公网安备 44011602000060号    粤ICP备15103669号\'\'\'
print(re.findall(\'(\\d{3,4})-(\\d{6,8})\',str))

3. 用正则表达式进行英文分词。re.split(\'\',news)

string = "Today,we have a lot of homework"
print(re.split(\',|\\s\',string))

4. 使用正则表达式取得新闻编号

newsurl = "http://news.gzcc.cn/html/2018/xiaoyuanxinwen_0404/9183.html"
newID = re.match(\'http://news.gzcc.cn/html/2018/xiaoyuanxinwen(.*).html\', newsurl).group(1).split("/")[1]
print(newID)

5. 生成点击次数的Request URL

url = "http://oa.gzcc.cn/api.php?op=count&id={}&modelid=80".format(newID)
print(url)

6. 获取点击次数

newsurl = "http://news.gzcc.cn/html/2018/xiaoyuanxinwen_0404/9183.html"
newID = re.match(\'http://news.gzcc.cn/html/2018/xiaoyuanxinwen(.*).html\', newsurl).group(1).split("/")[1]
url = "http://oa.gzcc.cn/api.php?op=count&id={}&modelid=80".format(newID)
contact = requests.get(url)
count = contact.text.split(".html")[-1].lstrip("(\'").rstrip("\');")
print(count)

7. 将456步骤定义成一个函数 def getClickCount(newsUrl):

import re
def getClickCount():
    newUrl = "http://news.gzcc.cn/html/2018/xiaoyuanxinwen_0404/9183.html"
    newsId = re.findall("\\_(.*).html",newUrl)[0].split("/")[-1];
    res = requests.get("http://oa.gzcc.cn/api.php?op=count&id= {}&modelid=80".format(newsId))
    return int(res.text.split(".html")[-1].lstrip("(\'").rsplit("\');")[0])

8. 将获取新闻详情的代码定义成一个函数 def getNewDetail(newsUrl):

def getNewDetail(newsUrl):
    detail_res = requests.get(newsUrl)
    detail_res.encoding = "utf-8"
    detail_soup = BeautifulSoup(detail_res.text, "html.parser")
    print(detail_soup.select("#content")[0].text)  # 正文
 
    print(time, title, description, newsUrl)
 
    content = detail_soup.select("#content")[0].text
    info = detail_soup.select(".show-info")[0].text
    date_time = info.lstrip(\'发布时间:\')[:19]
    print(info)

9. 取出一个新闻列表页的全部新闻 包装成函数def getListPage(pageUrl):

def getlist(url):
   for news in soup.select("li"):
        if len(news.select(".news-list-title"))>0:  #排除为空的li
            time = news.select(".news-list-info")[0].contents[0].text
            title = news.select(".news-list-title")[0].text
            description = news.select(".news-list-description")[0].text
            detail_url = news.select(\'a\')[0].attrs[\'href\']
            print(time, title, description, detail_url)

10. 获取总的新闻篇数，算出新闻总页数包装成函数def getPageN():

def getPageN(url):
    res = requests.get(url)
    res.encoding = \'utf-8\'
    soup = BeautifulSoup(res.text, \'html.parser\')
    return int(soup.select(".a1")[0].text.rstrip("条"))//10+1

11. 获取全部新闻列表页的全部新闻详情。

def getall(url):
   for num in range(2,getPageN(url)):
     listpageurl="http://news.gzcc.cn/html/xiaoyuanxinwen/{}.html".format(num)
     getlist(listpageurl)
     getNewDetail(listpageurl)