使用正则表达式匹配函数时字符串对象错误

Question

import requests
from bs4 import BeautifulSoup
import re

search = "bolån"
goog_search = "https://www.google.se/search?source=hp&ei=3_l6WsHAKMiasgHf26zYBQ&q=" + search

r = requests.get(goog_search)
soup = BeautifulSoup(r.text, "html.parser")
elements = soup.find_all('cite', {'class': '_WGk'})
f = open('urls.txt','w')

pattern=r'((https?|ftp):\/\/|\b(?:[a-z\d]+\.))(([^\s()<>]+|\((?:[^\s()<>]+|(?:\([^\s()<>]+\)))?\))+(?:\(([^\s()<>]+|(\(?:[^\s()<>]+\)))?\)|[^\s`!()\[\]{};:<>]))?'
prog = re.compile(pattern)

for tag in elements:
    result = prog.match(pattern, str(tag))
    print(result)

当我在字符串上使用正则表达式时，无法摆脱此错误，以获取网址。

这是我得到的错误：

for tag in elements:
---> 17     result = prog.match(pattern, str(tag))
     18     print(result)

TypeError: 'str' object cannot be interpreted as an integer

Answer 1

来自python documentation似乎你混合了两种语法

  

序列

prog = re.compile(pattern)
result = prog.match(string)

  

相当于

result = re.match(pattern, string)

string必须传递给prog.match而不是pattern，所以只需

prog.match(str(tag))