如何搜索在python

Question

我使用python3.5.1和BeautifulSoup 我想用正則表達式來搜索特定鏈路刮網站使用正則表達式的特定鏈接： 我的代碼：

from bs4 import BeautifulSoup 
import urllib.request 
import re 
r = urllib.request.urlopen('http://i.cantonfair.org.cn/en/expexhibitorlist.aspx?categoryno=404').read() 
soup = BeautifulSoup(r,"html.parser") 
links = soup.find_all("a", href=re.compile(r"ExpExhibitorList\.aspx\?categoryno=[0-9]+"))  
linksfromcategories = ([link["href"] for link in links]) 
print(linksfromcategories) 

我得到所有的類似鏈接

['/cn/ExpExhibitorList.aspx?categoryno=432', 'ExpExhibitorList.aspx?categoryno=432003'] 

但我不想

'/cn/ExpExhibitorList.aspx?categoryno=432' 

待檢索

Answer 1

只需在您的正則表達式中使用錨。

links = soup.find_all("a", href=re.compile(r"^ExpExhibitorList\.aspx\?categoryno=[0-9]+$")) 

這將符合所有a標籤，其具有由上述正則表達式匹配的精確值。