BeautifulSoup支持大部分的CSS选择器，其语法为：向tag或soup对象的.select()方法中传入字符串参数，选择的结果以列表形式返回。
tag.select("string")
BeautifulSoup.select("string")
源代码示例：
html = """
<html>
<head>
<title>The Dormouse's story</title>
</head>
<body>
<p class="title" name="dromouse">
<b>The Dormouse's story</b>
</p>
<p class="story">
Once upon a time there were three little sisters; and their names were
<a class="mysis" href="http://example.com/elsie" id="link1">
<b>the first b tag<b>
Elsie
</a>,
<a class="mysis" href="http://example.com/lacie" id="link2" myname="kong">
Lacie
</a>and
<a class="mysis" href="http://example.com/tillie" id="link3">
Tillie
</a>;and they lived at the bottom of a well.
</p>
<p class="story">
myStory
<a>the end a tag</a>
</p>
<a>the p tag sibling</a>
</body>
</html>
"""
soup = BeautifulSoup(html,'lxml')
1、通过标签选择
# 选择所有title标签
soup.select("title")
# 选择所有p标签中的第三个标签
soup.select("p:nth-of-type(3)") 相当于soup.select(p)[2]
# 选择body标签下的所有a标签
soup.select("body a")
# 选择body标签下的直接a子标签
soup.select("body > a")
# 选择id=link1后的所有兄弟节点标签
soup.select("#link1 ~ .mysis")
# 选择id=link1后的下一个兄弟节点标签
soup.select("#link1 + .mysis")
2、通过类名查找
# 选择a标签，其类属性为mysis的标签
soup.select("a.mysis")
3、通过id查找
# 选择a标签，其id属性为link1的标签
soup.select("a#link1")
4、通过【属性】查找，当然也适用于class
# 选择a标签，其属性中存在myname的所有标签
soup.select("a[myname]")
# 选择a标签，其属性href=http://example.com/lacie的所有标签
soup.select("a[href='http://example.com/lacie']")
# 选择a标签，其href属性以http开头
soup.select('a[href^="http"]')
# 选择a标签，其href属性以lacie结尾
soup.select('a[href$="lacie"]')
# 选择a标签，其href属性包含.com
soup.select('a[href*=".com"]')
# 从html中排除某标签，此时soup中不再有script标签
[s.extract() for s in soup('script')]
# 如果想排除多个呢
[s.extract() for s in soup(['script','fram']
5、获取文本及属性
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>; </p> and they lived at the bottom of a well. <p class="story">...</p> </body> """ from bs4 import BeautifulSoup ''' 以列表的形式返回 ''' soup = BeautifulSoup(html_doc, 'html.parser') s = soup.select('p.story') s[0].get_text() # p节点及子孙节点的文本内容 s[0].get_text("|") # 指定文本内容的分隔符 s[0].get_text("|", strip=True) # 去除文本内容前后的空白 print(s[0].get("class")) # p节点的class属性值列表（除class外都是返回字符串）
6、UnicodeDammit.detwingle() 方法只能解码包含在UTF-8编码中的Windows-1252编码内容,
new_doc = UnicodeDammit.detwingle(doc) print(new_doc.decode("utf8")) # ☃☃☃“I like snowmen!”
在创建 BeautifulSoup 或 UnicodeDammit 对象前一定要先对文档调用 UnicodeDammit.detwingle() 确保文档的编码方式正确.如果尝试去解析一段包含Windows-1252编码的UTF-8文档,就会得到一堆乱码,比如: ☃☃☃“I like snowmen!”.
7、其它：
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>; </p> and they lived at the bottom of a well. <p class="story">...</p> </body> """ from bs4 import BeautifulSoup ''' 以列表的形式返回 ''' soup = BeautifulSoup(html_doc, 'html.parser') soup.select('title') # title标签 soup.select("p:nth-of-type(3)") # 第三个p节点 soup.select('body a') # body下的所有子孙a节点 soup.select('p > a') # 所有p节点下的所有a直接节点 soup.select('p > #link1') # 所有p节点下的id=link1的直接子节点 soup.select('#link1 ~ .sister') # id为link1的节点后面class=sister的所有兄弟节点 soup.select('#link1 + .sister') # id为link1的节点后面class=sister的第一个兄弟节点 soup.select('.sister') # class=sister的所有节点 soup.select('[class="sister"]') # class=sister的所有节点 soup.select("#link1") # id=link1的节点 soup.select("a#link1") # a节点，且id=link1的节点 soup.select('a[href]') # 所有的a节点，有href属性 soup.select('a[href="http://example.com/elsie"]') # 指定href属性值的所有a节点 soup.select('a[href^="http://example.com/"]') # href属性以指定值开头的所有a节点 soup.select('a[href$="tillie"]') # href属性以指定值结尾的所有a节点 soup.select('a[href*=".com/el"]') # 支持正则匹配