Question

我有这个python代码，但是当我运行它时，只打印出第一个目标，这是我的python代码：

def get_next_target(S):
    start_link = S.find('<a href=')
    start_quote = S.find('"', start_link)
    end_quote = S.find('"', start_quote + 1)
    url = S[start_quote + 1:end_quote]
    print url
    return url, end_quote

get_next_target(S)

变量S = '<susuds><a href="www.target1.com"/><ahsahsh><saudahsd><a href="www.target2.com"/><p>sa</h1><a href="www.target3.com"/>＆＃39;

我想要的是打印出三个目标，而不是只打印第一个目标，为什么会这样？

Answer 1

我认为您应该使用BeautifulSoup从html / xml中提取信息。

In [1]: from bs4 import BeautifulSoup

In [2]: html = '''<susuds><a href="www.target1.com"/><ahsahsh><saudahsd><a href=
   ...: "www.target2.com"/><p>sa</h1><a href="www.target3.com"/>'''

In [3]: soup = BeautifulSoup(html, 'lxml')

In [4]: for a in soup.find_all('a'):
   ...:     print(a['href'])
   ...:     
www.target1.com
www.target2.com
www.target3.com

Answer 2

如果您在逻辑上想要在不使用任何特殊模块的情况下实现此目的，那么下面的代码将会这样做。

import re
import sys
S = '<susuds><a href="www.target1.com"/><ahsahsh><saudahsd><a href="www.target2.com"/><p>sa</h1><a href="www.target3.com"/>'
abc = []
def get_next_target(S):
    search_index = [i.start() for i in re.finditer('<a href=', S)]
    for j in range(len(search_index)):
        if ( j == len(search_index)-1):
            A =S[ search_index[j]:len(S) ]
            search_start_index = A.find('"')
            search_end_index = A.rfind('"')
            start_final = search_index[j] + search_start_index  + 1
            start_end = search_index[j] + search_end_index
            final_result = S[ start_final:start_end ]
            abc.append(final_result)
            print abc
        else:
            A = S[ search_index[j]:search_index[j+1] ]
            search_start_index = A.find('"')
            search_end_index = A.rfind('"')
            start_final = search_index[j] + search_start_index + 1 
            start_end = search_index[j] + search_end_index
            final_result = S[ start_final:start_end ]
            abc.append(final_result)`enter code here`
get_next_target(S)

注意：如果您不想将结果附加到列表中，请将最后两行if和else语句替换为＆＃34; print final_result＆＃34;。enter code here

函数调用问题

2 个答案: