爬虫——json、jsonpath、xpath模糊查询

发现一个问题，之前爬的内容写入文件的方式错了，应该是“wb"! 啊，居然才发现，太蠢了！

json.dump() : 将python内置类型序列转化为python对象后写入文件

json.load() : 将json形式的字符串元素转化成python类型

import urllib.request
import json
import jsonpath

url = "https://www.lagou.com/lbs/getAllCitySearchLabels.json"
headers = {"User-Agent": "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36"}

request = urllib.request.Request(url, headers=headers)
html = urllib.request.urlopen(request).read()

# html.decode("utf-8")
# html = bytes(html,  encoding="utf-8")
# html = html.decode("gbk")
with open("lagou.txt","wb") as f:
    f.write(html)

# 把json形式的字符串转换成python形式的Unicode字符串
unicodestr = json.loads(html)

city_list = jsonpath.jsonpath(unicodestr, "$..name")

for item in city_list:
    print(item)
# dumps()默认中文为ascii编码格式
# dumps直接操作,返回Unicode字符串
array = json.dumps(city_list, ensure_ascii=False)

with open("lagou.json","wb") as f:
    # unicode转化为utf-8
    f.write(array.encode("utf-8"))

xpath模糊查询：

//div[contains(@要查找的标签或者属性名，要匹配的字符串)]