上一篇笔记详细介绍了find_all()方法的name,attr,recursive,string,limit参数。
接下来的find()，find_parents()等方法搜索参数和find_all()方法类似，只是搜索目标会不同。
1 find()
find_all() and find() work their way down the tree, looking at tag’s descendants.
Signature: find(name, attrs, recursive, string, **kwargs)
>>> html_doc = """ <html><head><title>The Dormouse's story</title></head> <body> <p class="title"><b>The Dormouse's story</b></p> <p class="story">Once upon a time there were three little sisters; and their names were <a href="http://example.com/elsie" class="sister" id="link1">Elsie</a>, <a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and <a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>; and they lived at the bottom of a well.</p> <p class="story">...</p> """ >>> from bs4 import BeautifulSoup >>> soup = BeautifulSoup(html_doc,"html.parser") >>> soup.find('Alice') #返回None >>> >>> soup.find_all('Alice') #返回空列表 [] >>> >>> soup('Alice') #BeautifulSoup会默认使用find_all()方法。 [] >>> soup('title') [<title>The Dormouse's story</title>] >>> soup.title(text=True) ["The Dormouse's story"] >>> soup.title.find_all(text=True) ["The Dormouse's story"] >>>2 find_parents() and find_parent()
find_parents() and find_parent() work their way up the tree, looking at a tag’s (or a string’s) parents.
Signature: find_parents(name, attrs, string, limit, **kwargs) Signature: find_parent(name, attrs, string, **kwargs)
>>> a_string = soup.find(text="Lacie") # 从文档的一个叶节点开始 >>> a_string 'Lacie' >>> >>> a_string.find_parents('a') ## direct parent [<a class="sister" href="http://example.com/lacie" id="link2">Lacie</a>] >>> a_string.find_parents('p') ##indirect parent [<p class="story">Once upon a time there were three little sisters; and their names were <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a>, <a class="sister" href="http://example.com/lacie" id="link2">Lacie</a> and <a class="sister" href="http://example.com/tillie" id="link3">Tillie</a>; and they lived at the bottom of a well.</p>] >>> >>> a_string.find_parents('p',class_='sister') [] >>> a_string.find_parents(class_="sister") [<a class="sister" href="http://example.com/lacie" id="link2">Lacie</a>]3 find_next_siblings() and find_next_sibling()
Iterate over the rest of an element’s siblings in the tree. (搜索后面的兄弟节点) The find_next_siblings() method returns all the siblings that match, and find_next_sibling() only returns the first one
Signature: find_next_siblings(name, attrs, string, limit, **kwargs) Signature: find_next_sibling(name, attrs, string, **kwargs)
>>> first_link = soup.a >>> first_link <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a> >>> first_link.find_next_siblings('a') [<a class="sister" href="http://example.com/lacie" id="link2">Lacie</a>, <a class="sister" href="http://example.com/tillie" id="link3">Tillie</a>] >>> >>> first_story_paragraph = soup.find("p","story") >>> first_story_paragraph <p class="story">Once upon a time there were three little sisters; and their names were <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a>, <a class="sister" href="http://example.com/lacie" id="link2">Lacie</a> and <a class="sister" href="http://example.com/tillie" id="link3">Tillie</a>; and they lived at the bottom of a well.</p> >>> >>> first_story_paragraph.find_next_siblings('p') [<p class="story">...</p>] >>>4 find_previous_siblings() and find_previous_sibling()
Iterate over an element’s siblings that precede it in the tree.（搜索前面的兄弟节点） The find_previous_siblings() method returns all the siblings that match, and find_previous_sibling() only returns the first one.
Signature: find_previous_siblings(name, attrs, string, limit, **kwargs) Signature: find_previous_sibling(name, attrs, string, **kwargs)
>>> second_link = soup.find('a',id='link2') >>> second_link.find_previous_siblings('a') [<a class="sister" href="http://example.com/elsie" id="link1">Elsie</a>] >>> >>>5 find_all_next() and find_next()
Iterate over whatever tags and strings that come after it in the document. The find_all_next() method returns all matches, and find_next() only returns the first match.
Signature: find_all_next(name, attrs, string, limit, **kwargs) Signature: find_next(name, attrs, string, **kwargs)
>>> first_link = soup.find('a') >>> first_link <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a> >>> first_link.find_all_next() [<a class="sister" href="http://example.com/lacie" id="link2">Lacie</a>, <a class="sister" href="http://example.com/tillie" id="link3">Tillie</a>, <p class="story">...</p>] >>> first_link.find_all_next(text=True) ['Elsie', ',\n', 'Lacie', ' and\n', 'Tillie', ';\nand they lived at the bottom of a well.', '\n', '...', '\n'] >>> first_link.find_all_next('p') [<p class="story">...</p>] >>>6 find_all_previous() and find_previous()
Iterate over the tags and strings that came before it in the document. The find_all_previous() method returns all matches, and find_previous() only returns the first match.
Signature: find_all_previous(name, attrs, string, limit, **kwargs) Signature: find_previous(name, attrs, string, **kwargs)
>>> first_link.find_all_next('p') [<p class="story">...</p>] >>> first_link = soup.find('a') >>> first_link <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a> >>> >>> first_link.find_all_previous('p') [<p class="story">Once upon a time there were three little sisters; and their names were <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a>, <a class="sister" href="http://example.com/lacie" id="link2">Lacie</a> and <a class="sister" href="http://example.com/tillie" id="link3">Tillie</a>; and they lived at the bottom of a well.</p>, <p class="title"><b>The Dormouse's story</b></p>] >>> >>> first_link.find_all_previous('title') [<title>The Dormouse's story</title>] >>> >>> first_link.find_all_previous(text=True) ['Once upon a time there were three little sisters; and their names were\n', '\n', "The Dormouse's story", '\n', '\n', "The Dormouse's story", '\n'] >>> >>> first_link.find_previous() <p class="story">Once upon a time there were three little sisters; and their names were <a class="sister" href="http://example.com/elsie" id="link1">Elsie</a>, <a class="sister" href="http://example.com/lacie" id="link2">Lacie</a> and <a class="sister" href="http://example.com/tillie" id="link3">Tillie</a>; and they lived at the bottom of a well.</p> >>>