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BeautifulSoup的使用(三)

admin 12月 03, 2021 0

bs4的find_all的使用方法(重点)

from bs4 import BeautifulSoup
import re

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 href="http://example.com/elsie" class="sister" id="link1"><!-- E
lsie --></a>,
<a href="http://example.com/lacie" class="sister" id="link2">Lacie<
/a> and
<a href="http://example.com/tillie" class="sister" id="link3">Tilli
e</a>;
and they lived at the bottom of a well.</p>
<p class="story">...</p>
"""

soup = BeautifulSoup(html, "lxml")  # "lxml解析方式"
print soup.find("p")     # 找到第一个p标签
print soup.find_all("p")     # 找到所有p标签，列表形式返回
print soup.find_all("p")[2]     # 找到所有p标签，列表形式返回

for tag in soup.find_all(re.compile("^b")):  # 使用正则的方式进行匹配
    print tag.name
"""
<body>...</body>
<b>...</b>
"""

print soup.find_all(["title","b"])  # 按照列表进行搜索，只要有一个符合就返回数据
"""
[<title>The Dormouse's story</title>, <b>The Dormouse's story</b>]
"""

print soup.find_all(id="link2")
"""
[<a class="sister" href="http://example.com/lacie" id="link2">Lacie&lt;\n/a&gt; and\n</a>]
"""

print(soup.find_all(class_="sister")) # class特殊 使用class_
"""
[<a class="sister" href="http://example.com/elsie" id="link1"><!-- E\nlsie --></a>, <a class="sister" href="http://example.com/lacie" id="link2">Lacie&lt;\n/a&gt; and\n</a>, <a class="sister" href="http://example.com/tillie" id="link3">Tilli\ne</a>]
"""

print(soup.find_all(text="The"))
print(soup.find_all(text="The Dormouse's story"))
"""
精确的等于才能完成匹配
[]
[u"The Dormouse's story", u"The Dormouse's story"]
"""

print(soup.find_all("a",class_="sister")) # 限定查找a标签的class属性为sister的元素数据
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bs4的select的使用方法(重点)

from bs4 import BeautifulSoup
import re

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 href="http://example.com/elsie" class="sister" id="link1"><!-- E
lsie --></a>,
<a href="http://example.com/lacie" class="sister" id="link2">Lacie<
/a> and
<a href="http://example.com/tillie" class="sister" id="link3">Tilli
e</a>;
and they lived at the bottom of a well.</p>
<p class="story">...</p>
"""

soup = BeautifulSoup(html, "lxml")  # "lxml解析方式"
print soup.select("title")  # 按照标签的名字进行查找
print soup.select("a")  # 按照标签的名字进行查找,一次定位多个

print soup.select(".sister")   # 按照class进行查找
print soup.select("#link1")   # 按照id进行查找

print soup.select("p #link1")   # p标签内部的id进行查找
"""
[<a class="sister" href="http://example.com/elsie" id="link1"><!-- E\nlsie --></a>]
"""

print soup.select("head > title")  # 后代(层级关系)

print soup.select("a[class="sister"]")  # 标签为a的class=sister的元素
"""
[<a class="sister" href="http://example.com/elsie" id="link1"><!-- E\nlsie --></a>, <a class="sister" href="http://example.com/lacie" id="link2">Lacie&lt;\n/a&gt; and\n</a>, <a class="sister" href="http://example.com/tillie" id="link3">Tilli\ne</a>]
"""

print(soup.select("title")[0].get_text())   # 获取标签之间的内容
"""
The Dormouse's story
"""
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