Python_爬虫_urllib解析库

简介：提取网页保存到txt文件中 + 解析txt文件内容，取出内容

from urllib import request
import re.json

url="http://www.163.com"
response = request.urlopen(url).read().decode("gbk")
# 写入一个txt文件
with open("163/163.txt","w",encoding="gbk")as f:
    f.write(str(response))
# 读取,用json序列化后遍历出来，取出键里面的值
with open("163/163.txt",'r+',encoding="utf-8")as f:
    content=f.read()
c1=content.replace(" ",'').replace("
",'') #去掉空格、换行
c2="["+c1+"]"
cc=json.loads.(c2)  #序列化
for i in cc:
    print(x['title'])   #取出每个项里面“title”键的值
    print(x['docurl'])

简介：提取美团链接保存在一个txt文件中

#coding=utf-8
from urllib import request
from bs4 import BeautifulSoup
req=request.urlopen("http://hotel.meituan.com/xian/")
content=req.read().decode("utf8")
bsObj=BeautifulSoup(content,"html.parser")
pcontent=bsObj.findAll("a",{"class":"poi-title"})

i=1
with open("meituan/url.txt","a+",encoding="utf8") as f:
        for x in pcontent:
                f.write(x['href']+"
")    #取出 标签 里面的信息
                f.write(x.get_text())    #取出正文
                print("第"+'int(%s)'%(i)+"条url")
                i+=1

---

范例：功能实现后提高代码质量

#coding=utf-8
#获取当前地址下的所有酒店url地址
from urllib import request,error
from bs4 import BeautifulSoup
import json
for page in range(3):
        url="https://ihotel.meituan.com/hbsearch/HotelSearch?utm_medium=pc&version_name=999.9&cateId=20&attr_28=129&uuid=12B729E22135402D5CBC1432A179A735CF81DF50626153919EC2C66D46DCB233%401517811001478&cityId=42&offset="+str(page*20)+"&limit=20&startDay=20180205&endDay=20180205&q=&sort=defaults"
        try:
                req=request.urlopen(url)
                content=req.read().decode("utf8")
##                bsObj=BeautifulSoup(content,"html.parser")
##                pcontent=bsObj.findAll("a",{"class":"poi-title"})
                content_dict=json.loads(content)
                with open("meituan/url.txt","a+",encoding="utf8") as f:
                        for x in content_dict['data']['searchresult']:
                                print(x['poiid'])
                                hotel_url="http://hotel.meituan.com/%s/"%x['poiid']
                                f.write(hotel_url+"
")
        except error.URLError as e:
                print(e.reason)

urllib添加代理IP

# -*- coding: UTF-8 -*-
from urllib import request

if __name__ == "__main__":
    #访问网址
    url = 'http://2017.ip138.com/ic.asp'
    #url = 'http://www.whatismyip.com.tw'
    #这是代理IP
    proxy = {'http':'113.124.226.174:808'}
    #创建ProxyHandler
    proxy_support = request.ProxyHandler(proxy)
    #创建Opener
    opener = request.build_opener(proxy_support)
    #添加UserAngent
    opener.addheaders = [
        ('User-Agent','Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36'),
        ('Host','www.whatismyip.com.tw')    #这个网站能检测IP地址，所以用这个作为示例
    ]
    #安装OPener
    request.install_opener(opener)
    #使用自己安装好的Opener
    response = request.urlopen(url)
    #读取相应信息并解码
    html = response.read().decode("gbk")
    #打印信息
    print(html)