无法使用post请求分析某些搜索结果中的表格内容

Question

我正在尝试使用下面的脚本从a webpage获取一些表格内容。要手动填充内容，必须在点击Submit按钮之前从this image中显示的下拉列表中选择选项。我尝试相应地模拟post http请求。然而，我可能出了什么问题，这就是为什么脚本不起作用。具体来说，this is我试图获取的内容

我就是这样尝试的：

import requests
from bs4 import BeautifulSoup

URL = 'https://www.lgindiasocial.com/microsites/brand-store-web-five/locate.aspx'

headers = {
    'x-microsoftajax': 'Delta=true',
    'origin': 'https://www.lgindiasocial.com',
    'content-type': 'application/x-www-form-urlencoded; charset=UTF-8',
    'referer': 'https://www.lgindiasocial.com/microsites/brand-store-web-five/locate.aspx',
}

with requests.Session() as s:
    s.headers['User-Agent'] = 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.89 Safari/537.36'
    r = s.get(URL)
    soup = BeautifulSoup(r.text,"lxml")
    payload = {i['name']:i.get('value','') for i in soup.select('input[name]')}
    payload['ScriptManager1'] = 'UpdatePanel1|btnsubmit'
    payload['ddlState:'] = 'Assam'
    payload['ddlCity'] = 'Golaghat'
    payload['ddllocation'] = 'Golaghat'
    s.headers.update(headers)
    r = s.post(URL,data=payload)
    soup = BeautifulSoup(r.text,"lxml")
    item = soup.select_one("table")
    print(item)

当我运行脚本时，我没有得到任何输出

如何使用post请求从搜索结果中获取表格内容？

编辑：如果我直接从dev工具复制the content个有效负载，并在有效负载中使用相同的内容，我会得到想要的结果

import requests
from bs4 import BeautifulSoup

URL = 'https://www.lgindiasocial.com/microsites/brand-store-web-five/locate.aspx'

payload = "ScriptManager1=UpdatePanel1%7Cbtnsubmit&hidcity=&ddlState=Assam&ddlCity=Golaghat&ddllocation=Golaghat&__EVENTTARGET=&__EVENTARGUMENT=&__LASTFOCUS=&__VIEWSTATE=M%2BqldpZhV90EX2sawXMrHD7jYtOMXnrPuP8XfVtS21GKmxK0YYuBnqm3I7tU%2BKMtFGZgzWpsYK%2FYJtfTBUK%2F0WobR21tjbWjdrZiXS5FlLcS6qgYMNKfqyZRcK13dbz667H7T6QZqpITTRSqsM%2BrM91VW989KXoknFdx0H6EkRFCJRu4WsBsUxeJnd5Lf5IAUN%2BTNKDYE5GuclDNKnmU1pMmHhrjKQysvYtw8cjD5DdDkNb7NDkLiVxm7DISyXZtVJyOBV6dFa%2Blm1%2FR9M7F2nyepARAl0XIiNP9dhFvomLNdlP%2BU%2FNyllJ5IXW4D%2Fl5Kfx5yaRP8XSKURtAc915i%2F2T48a0dyAR42tJ40eit1IWs7MCwgesNtF35zkuKN1SRhyhHqcnKjcMYW%2BkLqKsLvKpLQcDuXrIAzYyqlgJZ%2FlBQJo%2BiM4tTOH4mEqDkSZW%2Fk94KX1OM70s9%2FS%2Fd5trrHIgNoKw1bCRI8IQ41ZEicMsJPTp67KnqoMZz0F0cCmo%2F49zYkuHw0kqaZmKCrRUNW8Xcr%2F5A3AfNg%2FB8WURD0g2x%2BwzcLXDcVCJ6ngf0LdOc%2BTppM6EOZpTGJGjjDqK116tzWAOPfiJHgBuIPkiZJTaEHnwwjcYXuuLN%2FTgPFUJkXVjBSyRdCnPXsebInNd4Wsu2lnNdwZUO3rnNuu5eY%2FHf7YemcmCEzji%2FxLG%2FynnG0sG61TC1bJCyFw2E3V6ZGshbuqDfh7QQyxqPDEt2uaCN7s%2FOZ%2FwiXeVY2henUVBZSVrxUvF6QT0eO4SIY0OlNYBLK7cO4YG4zC0tURSBr7lZwR%2B%2FowLieNGSO7sOeLQVwL71GKnzBAOZVQH1hw%2B8FIRPoc0pn3v7RjK5CMgTtrZlar67Cv1lTi2nUyAIpX%2BhGkaQeOsg%2ByaIqDIo%2FWwcrg9VV9QP%2FdmwP8hTtq3KTVs0Ncja4Yvizm12BkEwWtMJ9fqzLBXt%2F2J2EjsG7GudgXypwSU7U8oY%2Fq%2BCk93y%2FeTr1ftEFbpGRTRm4hNVXeoCYRyuJceU%2BvO4U5E29ZPqBIolidYtKKH7lnRxKNk2BHtY93VNHPZEjTEDnHcGbgtHmxlBjHRQZlzJKWTjY5ccdFABihGx%2FzY0VCwaehpx2BWxy5qXqW1fX7e5uxxxHteYVt7YyrzYPsX%2B%2FlKiYwt23fsJzmmVkHwmu5%2FTSk1Ms9yJmBE%2B8pEF%2Bum01L8jRH4zxyTaD4s779uLZwLAUUzpi5cfseKTrjGv7uNjCpNci9BXbSdCdqrKa8aPiJX0lWUH9zid%2B8Jc7Jhx%2Bb6nzJpbZ8E9sPpUlcHVGUSzqixsiK91W%2FDDk2LCOvTqJJ9JXmy5cwRhL9r95okWq%2BDImTetFhdYk9%2F9VH3JsACpv4dqqdviEjjFpvmEp7SBMLSWw7toPUIRortPtriz3u9velTqNpHgmbmig8Znb%2F4Q8JrYfjPZzfRxN%2FuQXQyxUNUY2IsYbC5Bm7JWTMZe869muBdE%2FlMLujUkOFCXaOwZXuZHbr7neq0nro3RvYUggBLqxGFlG1Bp52iDNklcx8nfjVMOhOybfCMcxz6mq4Ew2hdLv4IslLRawI5u%2FPQe0vu0TG9LeBeR6Ok1sf72rWpvhD6yl4GTy8oJC1UglabWo8i5aMprxxAWuz%2BzLzizI3aRTQsl1MFKsD9gIGZsaFNAIb7gEgFgw%2B%2BSjTGR51mGES3sOUYXscIJVBciBs3F9vnr8u5gfKD3hLwqvc4djKMBxVQfjLEs%2FQwb7mlOx8XodaV6uOrkiZpw2WZNja5RPBIp4VXeXKXIxqBNsNA4eGT%2Bx2b2JadVB8%3D&__VIEWSTATEGENERATOR=06ED1D24&__VIEWSTATEENCRYPTED=&__ASYNCPOST=true&btnsubmit=Submit"

with requests.Session() as s:
    s.headers['User-Agent'] = 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.89 Safari/537.36'
    s.headers.update({'content-type':'application/x-www-form-urlencoded; charset=UTF-8'})
    r = s.post(URL,data=payload)
    soup = BeautifulSoup(r.text,"lxml")
    item = soup.select_one("table")
    print(item)

Answer 1

首先，在代码中输入一个小的输入错误，（在那里加上冒号）

payload['ddlState:'] = 'Assam'

更大的问题在于页面的构造方式。该页面有三个下拉列表，这些下拉列表发送POST请求。每个POST请求都返回一个修改的_VIEWSTATE，该状态需要包含在后续请求的标头中

在您的代码中，您仅从原始GET请求的输入[form]获取_VIEWSTATE，您需要从上一个POST请求获取_VIEWSTATE。因此，以下措施应该有效：

with requests.Session() as s:
    s.headers['User-Agent'] = 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.89 Safari/537.36'
    r = s.get(URL)
    soup = BeautifulSoup(r.text, "lxml")

    # first POST = Select State
    payload = {i['name']: i.get('value', '') for i in soup.select('input[name]')}
    payload['ScriptManager1'] = 'UpdatePanel1|btnsubmit'
    payload['ddlState'] = 'Assam'
    payload['ddlCity'] = 'Select City'
    payload['ddllocation'] = 'Select Location'
    payload['__EVENTTARGET'] = 'ddlState'
    r = s.post(URL, data=payload)
    soup = BeautifulSoup(r.text, "lxml")

    # second POST = Select City
    payload = {i['name']: i.get('value', '') for i in soup.select('input[name]')}
    payload['ScriptManager1'] = 'UpdatePanel1|btnsubmit'
    payload['ddlCity'] = 'Golaghat'
    payload['ddllocation'] = 'Select Location'
    payload['__EVENTTARGET'] = 'ddlCity'
    r = s.post(URL, data=payload)
    soup = BeautifulSoup(r.text, "lxml")

    # third POST = Select Location
    payload = {i['name']: i.get('value', '') for i in soup.select('input[name]')}
    payload['ScriptManager1'] = 'UpdatePanel1|btnsubmit'
    payload['ddlCity'] = 'Golaghat'
    payload['ddllocation'] = 'Golaghat'
    payload['__EVENTTARGET'] = ''

    s.headers.update(headers)
    r = s.post(URL, data=payload)
    soup = BeautifulSoup(r.text, "lxml")
    item = soup.select_one("table")
    print(item)

这段代码还有一些优化的空间。我试图使问题透明化