xpath实战

#  1、爬取58二手房信息
import  requests
from lxml import etree
#需求：爬取58二手房中的房源信息
if __name__ == '__main__':
    #爬取到页面源码数据
    url ="https://bj.58.com/ershoufang/"
    # 进行UA伪装
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0'
    }
    page_text = requests.get(url = url,headers=headers).text
    # 数据解析
    tree = etree.HTML(page_text)
    # 存储的是li标签对象
    li_list = tree.xpath('//ul[@class="houst-list-wrap"]/li')
    fp = open('58.txt','w',encoding='utf-8')
    for li in li_list:
        # ./ 就代表li
        #局部解析   一个要加上.
        title = li.xpath('./div[2]/h2/a/text()')[0]
        print(title,'over')
        fp.write(title,'\n')
2、解析下载图片信息  http://pic.netbian.com/4kmeinv/
    解决乱码的两种方法：
      #1、response.encoding = 'utf-8'
      #2、通用的处理中文乱码的解决方案
　　　img_name = img_name.encode('iso-8859-1').decode('gbk')

import  requests
from lxml import etree
import os
#需求：爬取58二手房中的房源信息
if __name__ == '__main__':
    #爬取到页面源码数据
    url ="http://pic.netbian.com/4kmeinv/"
    # 进行UA伪装
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0'
    }
    response = requests.get(url =url,headers = headers)
    #response.encoding = 'utf-8'
    page_text = response.text

    #数据解析：src的属性值  alt属性
    tree = etree.HTML(page_text)
    li_list = tree.xpath('//div[@class="slist"]/ul/li')
    if not os.path.exists('./piclibs'):
        os.mkdir('./piclibs')
    for li in li_list:
        img_src = 'http://pic.netbian.com'+li.xpath('./a/img/@src')[0]
        img_name = li.xpath('./a/img/@alt')[0]+'.jpg'
        #通用的处理中文乱码的解决方案
        img_name = img_name.encode('iso-8859-1').decode('gbk')
        #print(img_name,img_src)
        #请求图片数据进行持久化存储
        img_data = requests.get(url=img_src,headers = headers).content
        img_path = 'piclibs/'+img_name
        with open(img_path,'wb') as fp:
            fp.write(img_data)
            print(img_name,'下载成功！！！')
3、全国城市 历史检测数据  https://www.aqistudy.cn/historydata/

import  requests
from lxml import etree
import os
#需求：解析出所有城市名称
if __name__ == '__main__':
    #爬取到页面源码数据
    url ="https://www.aqistudy.cn/historydata/"
    # 进行UA伪装
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0'
    }
    page_text = requests.get(url =url,headers = headers).text
    tree = etree.HTML(page_text)
    #解析热门城市和所有城市对应的a标签
    # div[@class="bottom"]/ul/li/a  热门城市a标签的层级关系
    # div[@class="bottom"]/ul/div[2]/li/a  全部城市a标签的层级关系
    all_city_names = []
    a_list = tree.xpath('//div[@class="bottom"]/ul/li/a | //div[@class="bottom"]/ul/div[2]/li/a')
    for a in a_list:
        city_name = a.xpath('./text()')[0]
        all_city_names.append(city_name)
    print(all_city_names,len(all_city_names))

4、获取简历   sc.chinaz.com  免费简历