如果站点有两个链接，一个我想要，另一个我不想要，如何从站点中提取特定链接？

Question

<td>
  <input type="hidden" name="ctl00$ContentPlaceHolder1$dlstCollege$ctl01$hdnInstituteId" id="ContentPlaceHolder1_dlstCollege_hdnInstituteId_1" value="866  " />
  <a id="ContentPlaceHolder1_dlstCollege_hlpkInstituteName_1" href="CollegeDetailedInformation.aspx?Inst=866  ">A.N.A INSTITUTE OF PHARMACEUTICAL SCIENCES & RESEARCH,BAREILLY (866)</a>

  <br />
  <b>Location:</b>
  <span id="ContentPlaceHolder1_dlstCollege_lblAddress_1">13.5 km Bareilly - Delhi road, near rubber factory agras road ,Bareilly</span>

  <br />
  <b>Course:</b>
  <span id="ContentPlaceHolder1_dlstCollege_lblCourse_1">B.Pharm,</span>
  <br />
  <b>Category:</b>
  <span id="ContentPlaceHolder1_dlstCollege_lblInstituteType_1">Private</span>
  <br />
  <b>Web Address:</b>

  <a id="lnkBtnWebURL" href='' target="_blank"></a>
  <br />
</td>
</tr>
<tr>
  <td>
    <input type="hidden" name="ctl00$ContentPlaceHolder1$dlstCollege$ctl02$hdnInstituteId" id="ContentPlaceHolder1_dlstCollege_hdnInstituteId_2" value="486  " />
    <a id="ContentPlaceHolder1_dlstCollege_hlpkInstituteName_2" href="CollegeDetailedInformation.aspx?Inst=486  ">A.N.A.COLLEGE OF ENGINEERING & MANAGEMENT,BAREILLY (486)</a>

    <br />
    <b>Location:</b>
    <span id="ContentPlaceHolder1_dlstCollege_lblAddress_2">13.5 Km. NH-24, Bareilly-Delhi Highway, Near Rubber Factory, Bareilly</span>

    <br />
    <b>Course:</b>
    <span id="ContentPlaceHolder1_dlstCollege_lblCourse_2">B.Tech,M.Tech,</span>
    <br />
    <b>Category:</b>
    <span id="ContentPlaceHolder1_dlstCollege_lblInstituteType_2">Private</span>
    <br />
    <b>Web Address:</b>

    <a id="lnkBtnWebURL" href='http://www.anacollege.org/index.html' target="_blank">http://www.anacollege.org/index.html</a>
    <br />
  </td>
</tr>

我想从该网站中提取一个特定的URL（例如：CollegeDetailedInformation.aspx？Inst = 866），但是此代码具有两个我不想要的标签（例如：http://www.anacollege.org/index.html）。

res = requests.get('https://erp.aktu.ac.in/WebPages/KYC/CollegeList.aspx?City=&CType=&Cu=&Br=&Inst=&IType=')
soup = BeautifulSoup(res.content, 'html.parser')


table = soup.find("table", attrs = {'class':'table table-bordered table-responsive'})

pagelink = []
for anchor in table.findAll('a')[1:]:
        link = anchor['href']
        print(link)
        url = 'https://erp.aktu.ac.in/WebPages/KYC/'+ link
        pagelink.append(url)
print(pagelinks)

我写了这段代码，但是它正在提取所有链接

CollegeDetailedInformation.aspx?Inst=486  
http://www.anacollege.org/index.html
CollegeDetailedInformation.aspx?Inst=602  
http://www.aashlarbschool.com
CollegeDetailedInformation.aspx?Inst=032  
http://www.abes.ac.in
CollegeDetailedInformation.aspx?Inst=290  
http://www.abesit.in
CollegeDetailedInformation.aspx?Inst=913  
http://www.abesitpharmacy.in
CollegeDetailedInformation.aspx?Inst=643  
http://www.vitsald.com
CollegeDetailedInformation.aspx?Inst=1036 
http://www.abss.edu.in

我该如何解决，我只想要与CollegeDetailedInformation.aspx？Inst =的链接？部分。

Answer 1

我不了解Python，但一般规则是在for循环中填充一个数组，然后查找具有过滤器的子字符串，选择索引并获取该索引中的所有内容。

在循环外初始化并清空数组（如果在 Python），将其填充到循环中，然后执行类似in_array（用于 php）作为过滤器：CollegeDetailedInformation.aspx？Inst =?。

[这应该是一个好的开始，因为Python的高手会提供帮助。

Answer 2

尝试以下代码段。继续安装**lxml**库和pip，然后继续

import requests as rq
from bs4 import BeautifulSoup as bs

es = rq.get('https://erp.aktu.ac.in/WebPages/KYC/CollegeList.aspx?City=&CType=&Cu=&Br=&Inst=&IType=')
soup = bs(res.content, 'lxml')

table = soup.find("table", attrs = {'class':'table table-bordered table-responsive'})


links = [elem.strip() for anchor in table.findAll('a') for _,elem in anchor.attrs.items() if "=" in elem]

print(links)

Answer 3

作为查看大学详细信息的链接的锚点元素具有一个以id开头的ContentPlaceHolder1_dlstCollege_属性。因此，将其作为regex to the attrs argument的attrs传递：

find_all()

您也可以将其作为

import re

for anchor in table.findAll('a', attrs={"id": re.compile("^ContentPlaceHolder1_dlstCollege_.*")}):
    ...

传递给id keyword argument：

id

（（我会删除您放在末尾的find_all()，因为这可能会过滤掉您不需要的开头的链接。如果没有，请重新添加。）