用漂亮汤解析HTML以获得href后的链接
用漂亮汤解析HTML以获得href后的链接
提问于 2016-10-06 16:47:52
这是find_all('a') (很长)的结果：
/*
* 提示：该行代码过长，系统自动注释不进行高亮。一键复制会移除系统注释
* </a>, <a class="btn text-default text-dark clear_filters pull-right group-ib" href="#" id="export_dialog_close" title="Cancel"><span class="glyphicon glyphicon-remove"></span><span>Cancel</span></a>, <a href="/ais/index/port_moves/all/include_anchs:no/ship_type:7/_:3525d580eade08cfdb72083b248185a9/in_transit:no/time_interval:1474948800.0_1475035200.00/per_page:50/portname:NOVOROSSIYSK/cb:6651/move_type:1/sort:SHIPNAME/direction:asc">Vessel Name</a>, <a href="/ais/index/port_moves/all/include_anchs:no/ship_type:7/_:3525d580eade08cfdb72083b248185a9/in_transit:no/time_interval:1474948800.0_1475035200.00/per_page:50/portname:NOVOROSSIYSK/cb:6651/move_type:1/sort:TIMESTAMP_UTC/direction:asc">Timestamp</a>, <a href="/ais/index/port_moves/all/include_anchs:no/ship_type:7/_:3525d580eade08cfdb72083b248185a9/in_transit:no/time_interval:1474948800.0_1475035200.00/per_page:50/portname:NOVOROSSIYSK/cb:6651/move_type:1/sort:PORT_NAME/direction:asc">Port</a>, <a href="/ais/index/port_moves/all/include_anchs:no/ship_type:7/_:3525d580eade08cfdb72083b248185a9/in_transit:no/time_interval:1474948800.0_1475035200.00/per_page:50/portname:NOVOROSSIYSK/cb:6651/move_type:1/sort:MOVE_TYPE_NAME/direction:asc">Port Call type</a>, <a href="/ais/index/port_moves/all/include_anchs:no/ship_type:7/_:3525d580eade08cfdb72083b248185a9/in_transit:no/time_interval:1474948800.0_1475035200.00/per_page:50/portname:NOVOROSSIYSK/cb:6651/move_type:1/sort:ELAPSED/direction:asc">Time Elapsed</a>, <a href="/en/ais/details/ships/shipid:465271/imo:9495595/mmsi:373571000/vessel:SIDER%20LUCK/_:3525d580eade08cfdb72083b248185a9" title="View details for: SIDER LUCK">SIDER LUCK</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/163/port_name:MILAZZO/_:3525d580eade08cfdb72083b248185a9" title="View details for: MILAZZO">MILAZZO</a>, <a href="/en/ais/details/ships/shipid:288753/imo:9389693/mmsi:249474000/vessel:OOCL%20ISTANBUL/_:3525d580eade08cfdb72083b248185a9" title="View details for: OOCL ISTANBUL">OOCL ISTANBUL</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/17436/port_name:AMBARLI/_:3525d580eade08cfdb72083b248185a9" title="View details for: AMBARLI">AMBARLI</a>, <a href="/en/ais/details/ships/shipid:754480/imo:9045613/mmsi:636014098/vessel:TK%20ROTTERDAM/_:3525d580eade08cfdb72083b248185a9" title="View details for: TK ROTTERDAM">TK ROTTERDAM</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/3504/port_name:DILISKELESI/_:3525d580eade08cfdb72083b248185a9" title="View details for: DILISKELESI">DILISKELESI</a>, <a href="/en/ais/details/ships/shipid:412277/imo:9039585/mmsi:353430000/vessel:SEA%20AEOLIS/_:3525d580eade08cfdb72083b248185a9" title="View details for: SEA AEOLIS">SEA AEOLIS</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/1/port_name:PIRAEUS/_:3525d580eade08cfdb72083b248185a9" title="View details for: PIRAEUS">PIRAEUS</a>, <a href="/en/ais/details/ships/shipid:346713/imo:7614599/mmsi:273327300/vessel:SOLIDAT/_:3525d580eade08cfdb72083b248185a9" title="View details for: SOLIDAT">SOLIDAT</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/883/port_name:SEVASTOPOL/_:3525d580eade08cfdb72083b248185a9" title="View details for: SEVASTOPOL">SEVASTOPOL</a>, <a href="/en/ais/details/ships/shipid:752974/imo:9195298/mmsi:636011072/vessel:OCEANPRINCESS/_:3525d580eade08cfdb72083b248185a9" title="View details for: OCEANPRINCESS">OCEANPRINCESS</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/21780/port_name:EREGLI/_:3525d580eade08cfdb72083b248185a9" title="View details for: EREGLI">EREGLI</a>, <a href="/en/ais/details/ships/shipid:201260/imo:9385075/mmsi:235102768/vessel:EMERALD%20BAY/_:3525d580eade08cfdb72083b248185a9" title="View details for: EMERALD BAY">EMERALD BAY</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ships/shipid:418956/imo:9102746/mmsi:356579000/vessel:MSC%20DON%20GIOVANNI/_:3525d580eade08cfdb72083b248185a9" title="View details for: MSC DON GIOVANNI">MSC DON GIOVANNI</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/67/port_name:CONSTANTA/_:3525d580eade08cfdb72083b248185a9" title="View details for: CONSTANTA">CONSTANTA</a>, <a href="/en/ais/details/ships/shipid:748395/imo:9460734/mmsi:622121422/vessel:WADI%20SAFAGA/_:3525d580eade08cfdb72083b248185a9" title="View details for: WADI SAFAGA">WADI SAFAGA</a>, <a href="/en/ais/details/ports/767/port_name:NOVOROSSIYSK/_:3525d580eade08cfdb72083b248185a9" title="View details for: NOVOROSSIYSK">NOVOROSSIYSK</a>, <a href="/en/ais/details/ports/997/port_name:DAMIETTA/_:3525d580eade08cfdb72083b248185a9" title="View details for: DAMIETTA">DAMIETTA</a>
*/我想提取以/en/ais/details/ships/shipid:开头的字符串，例如：
<a href="/en/ais/details/ships/shipid:465271/imo:9495595/mmsi:373571000/vessel:SIDER%20LUCK/_:3525d580eade08cfdb72083b248185a9"我能够复制这些示例(找到具体的链接w/漂亮汤或如何让美丽的汤得到链接从href和班级？)，但我不愿使用regex。
到目前为止，我已经：
for i in ase: #ase is where the html is sotred
print(i.get('href')) #prints everysingle href. 简而言之，我的问题是如何只保留我感兴趣的字符串而不使用regex的href？
回答 3
Stack Overflow用户
回答已采纳
发布于 2016-10-06 19:09:48
@elethan的回答不是最好的。它将找到所有的链接，然后过滤掉它们的。为什么我们不直接得到我们需要的链接，没有额外的过滤- BeautifulSoup是非常有能力的：
prefix = "/en/ais/details/ships/shipid"
[a["href"] for a in soup("a", href=lambda x: x and x.startswith(prefix))]或者，与函数不同，您可以传递一个正则表达式模式来检查一个字符串是否以所需的子字符串开头：
pattern = re.compile(r"^/en/ais/details/ships/shipid")
[a["href"] for a in soup("a", href=pattern)]这里的^表示字符串的开头。
或者，我们甚至可以使用CSS选择器：
[a["href"] for a in soup.select('a[href^="/en/ais/details/ships/shipid"]')]^=是一个“开始-与”选择器。
Stack Overflow用户
发布于 2016-10-06 16:56:11
尝试以下列表理解：
[h.get('href') for h in ase if 'string' in h.get('href', '')] 这将为您提供一个仅包含包含子字符串'string'的链接的列表。
更新：
正如@PadraicCunningham在评论中指出的那样，如果h没有密钥'href'，'string' in h.get('href') (这是我最初答案的一部分)将引发TypeError --因为h将是<a>标记的表示，但肯定也是一种重要的可能性。为了允许这种可能性，您可以简单地向.get()传递一个''的默认参数，而不是在键不存在时返回None。
此外，我没有声称我的解决方案是最好的，它可能不是特别有效或优雅。然而，根据我对OPs问题的理解，这个解决方案是可行的，是最低限度的，而且很容易理解。
Stack Overflow用户
发布于 2016-10-06 17:00:30
我仍然建议您使用regex，因为它更简洁，并且在列表上节省了另一个循环。
import re
find_all('a', href=re.compile("/en/ais/details/ships/shipid:"))在文档中，您可以找到类似的解决方案。
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/39901554
复制相关文章
相似问题
腾讯云开发者
