爬虫程序1

Requests库

Requests库的作用就是请求网站获取网页数据的。让我们从简单的实例开始，讲解Requests库的使用方法。

import requests

res = requests.get('https://wuhan.anjuke.com/')

print(res)

#返回结果为<Response [200]>，说明请求网址成功，若为404,400则请求网址失败。

print(res.text)

#部分结果如图

BeautifulSoup库

BeautifulSoup库是一个非常流行的Python模块。通过BeautifulSoup库可以轻松的解析Requests库请求的网页，并把网页源代码解析为Soup文档，以便过滤提取数据。

import requests
from bs4 import BeautifulSoup
headers = {
    'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36'
}
res = requests.get('https://wuhan.anjuke.com/',headers=headers)
soup = BeautifulSoup(res.text,'html.parser')         #对返回的结果进行解析
print(soup.prettify())

 

Lxml库

Lxml库是基于libxm12这一个XML解析库的Python封装。该模块使用C语言编写，解析速度比BeautifulSoup更快

综合示例（一）——爬取北京地区短租房信息

 

（1）爬取小猪短租北京地区短租房13页的信息，通过手动浏览，以下为前四页的网址：

http://bj.xiaozhu.com/

http://bj.xiaozhu.com/search-duanzufang-p2-0/

http://bj.xiaozhu.com/search-duanzufang-p3-0/

http://bj.xiaozhu.com/search-duanzufang-p4-0/

只需更改p后面的数字即可，以此来构造出13页的网址。

（2）本次爬虫在详细页中进行，故先需爬取进入详细页的网址链接，进而爬取数据。

（3）需要爬取的信息有：

标题、地址、价格、房东名称、房东性别已经房东头像的链接

from bs4 import BeautifulSoup
import requests
import time

headers = {
'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36'
}

def judgment_sex(class_name):
if class_name == ['member_ico1']:
return '女'
else:
return '男'

def get_links(url):
wb_data = requests.get(url,headers=headers)
soup = BeautifulSoup(wb_data.text,'lxml')
links = soup.select('#page_list > ul > li > a')
for link in links:
href = link.get("href")
get_info(href)

def get_info(url):
wb_data = requests.get(url,headers=headers)
soup = BeautifulSoup(wb_data.text,'lxml')
tittles = soup.select('div.pho_info > h4')
addresses = soup.select('span.pr5')
prices = soup.select('#pricePart > div.day_l > span')
imgs = soup.select('#floatRightBox > div.js_box.clearfix > div.member_pic > a > img')
names = soup.select('#floatRightBox > div.js_box.clearfix > div.w_240 > h6 > a')
sexs = soup.select('#floatRightBox > div.js_box.clearfix > div.member_pic > div')
for tittle, address, price, img, name, sex in zip(tittles,addresses,prices,imgs,names,sexs):
data = {
'tittle':tittle.get_text().strip(),
'address':address.get_text().strip(),
'price':price.get_text(),
'img':img.get("src"),
'name':name.get_text(),
'sex':judgment_sex(sex.get("class"))
}
print(data)

if __name__ == '__main__':
urls = ['http://bj.xiaozhu.com/search-duanzufang-p{}-0/'.format(number) for number in range(1,14)]
for single_url in urls:
get_links(single_url)
time.sleep(2)