python学习（四）--POST请求

from urllib import request
import urllib
import re

#网页版有道翻译是ajax的post请求。

#浏览器请求地址http://fanyi.youdao.com/translate_o?smartresult=dict&smartresult=rule
#但是在抓取时，路径有所变化，具体原因不明。后续要了解下 translate_o -》 translate
url = "http://fanyi.youdao.com/translate?smartresult=dict&smartresult=rule"

#搜狗浏览器的   模拟浏览器
header = {"User-Agent":
    "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36 SE 2.X MetaSr 1.0"
        }
key = str(input("请输入要翻译的词语："))
#key = "中国"

#这个formData是浏览器发送请求copy过来的
formData = {
    "i":key,
    "from":"AUTO",
    "to":"AUTO",
    "smartresult":"dict",
    "client":"fanyideskweb",
    "salt":"15536694414373",
    "sign":"cddcc6c6092b57a04c546a2e075e2218",
    "ts":"1553669441437",
    "bv":"f355c521b6e13c15aa35c72a097b7786",
    "doctype":"json",
    "version":"2.1",
    "keyfrom":"fanyi.web",
    "action":"FY_BY_REALTlME",
   "typoResult":"false"
}

data = urllib.parse.urlencode(formData).encode(encoding = 'utf-8')
#当请求中存在data时就属于POST请求
req = request.Request(url, data = data , headers= header)

result = request.urlopen(req).read().decode()

print(result)

#用正则取出有用数
pattern = r'"tgt":"(.*?)"}'

va = re.findall(pattern, result)

print(va)