Python - BeautifulSoup，在标签内获取标签

Question

如何获得有关在标签内获取标签的信息？

出了td标签在这里：

<td scope="row"><a href="/Archives/edgar/data/1085621/000108562117000004/actuacorp12312016.htm">actuacorp12312016.htm</a></td> 

我想其中的href标记的价值，主要是HTM链接：

<a href="/Archives/edgar/data/1085621/000108562117000004/actuacorp12312016.htm">actuacorp12312016.htm</a> 

我有标签这样的：

<tr> 
<td scope="row">1</td> 
<td scope="row">10-K</td> 
<td scope="row"><a href="/Archives/edgar/data/1085621/000108562117000004/actuacorp12312016.htm">actuacorp12312016.htm</a></td> 
<td scope="row">10-K</td> 
<td scope="row">2724989</td> 
</tr> 
<tr class="blueRow"> 
<td scope="row">2</td> 
<td scope="row">EXHIBIT 21.1</td> 
<td scope="row"><a href="/Archives/edgar/data/1085621/000108562117000004/exhibit211q42016.htm">exhibit211q42016.htm</a></td> 
<td scope="row">EX-21.1</td> 
<td scope="row">21455</td> 
</tr> 
<tr> 
<td scope="row">3</td> 
<td scope="row">EXHIBIT 23.1</td> 
<td scope="row"><a href="/Archives/edgar/data/1085621/000108562117000004/exhibit231q42016.htm">exhibit231q42016.htm</a></td> 
<td scope="row">EX-23.1</td> 
<td scope="row">4354</td> 
</tr> 

查看所有标签的代码：

base_url = "https://www.sec.gov/Archives/edgar/data/1085621/000108562117000004/" \ 
       "0001085621-17-000004-index.htm" 
    response = requests.get(base_url) 
    base_data = response.content 
    base_soup = BeautifulSoup(base_data, "html.parser") 

Answer 1

您可以使用find_all先得到所有td标签，然后将这些标签中搜索锚：

links = [] 
for tag in base_soup.find_all('td', {'scope' : 'row'}): 
    for anchor in tag.find_all('a'): 
     links.append(anchor['href']) 

print(links) 

输出：

['/Archives/edgar/data/1085621/000108562117000004/actuacorp12312016.htm', 
'/Archives/edgar/data/1085621/000108562117000004/exhibit211q42016.htm', 
... 
'/Archives/edgar/data/1085621/000108562117000004/acta-20161231_lab.xml', 
'/Archives/edgar/data/1085621/000108562117000004/acta-20161231_pre.xml'] 

你可以写一点点过滤器删除那些非htm链接，如果你想：

filtered_links = list(filter(lambda x: x.endswith('.htm'), links)) 

---

要获得第一个链接，这里有一个稍微不同的版本，适合您的用例。

link = None 
for tag in base_soup.find_all('td', {'scope' : 'row'}): 
    children = tag.findChildren() 
    if len(children) > 0: 
     try: 
      link = children[0]['href'] 
      break 
     except: 
      continue 

print(link) 

这打印出'/Archives/edgar/data/1085621/000108562117000004/acta-20161231_pre.xml'。