Beautifulsoup 库详解
# -*- coding:utf8 -*-
# 工程路径：3.3 beautifulsoup库.py
# 工程日期：9/6/2019
# 工程目标：beautifulsoup使用详解
"""
bs支持lxml， HTML 解析， html5解析
"""
#%%
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"><!-- 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, 'lxml')
print(soup.prettify()) # 格式化html
print(soup.title.string) # 输出 title中内容
#%% 标签选择器
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"><!-- 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, 'lxml')
print(soup.title)
print(type(soup.title)) # 为bs4的元素tag类型
print(soup.head)
print(type(soup.head))
print(soup.p) # 只返回第一个匹配的p标签
#%% 获取标签的名称
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"><!-- 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, 'lxml')
print(soup.title.name) # 获取标签的名称
print(soup.p.name) # 获取p标签的名称
#%% 获取标签的属性
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"><!-- 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, 'lxml')
print(soup.p['name'])
print(soup.p.attrs['name']) # 获取属性
#%% 获取标签内的文本内容 .string
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"><!-- 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, 'lxml')
print(soup.p.string) # 获取标签内的文本内容
#%% 标签的嵌套选择
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"><!-- 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, 'lxml')
print(soup.head.title.string)
print(soup.body.p)
print(soup.body.a['href'])
print(soup.body.a['class'])
print(soup.body.a['id'])
#%% 子节点以及子孙节点的选择
html = """
<html>
<head>
<title>The Dormouse's story</title>
</head>
<body>
<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">
<span>Elsie</span>
</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, 'lxml')
print(soup.body.p.a['href'])
#print(soup.p.contents)
print(type(soup.p.contents))
for i in soup.p.contents:
print(i)
#%% .children 获取子节点 迭代器类型，
# 使用循环的方式才能取出内容
html = """
<html>
<head>
<title>The Dormouse's story</title>
</head>
<body>
<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">
<span>Elsie</span>
</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, 'lxml')
print(soup.p.children)
for i, child in enumerate(soup.p.children):
print(i, child)
#%% .descendents 获取所有的子孙节点
html = """
<html>
<head>
<title>The Dormouse's story</title>
</head>
<body>
<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">
<span>Elsie</span>
</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, 'lxml')
print(soup.p.descendants)
for i, decendant in enumerate(soup.p.descendants):
print(i, decendant) # 输出p标签的所有的子孙节点
#%% .parent父节点 .parents祖先节点
html = """
<html>
<head>
<title>The Dormouse's story</title>
</head>
<body>
<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">
<span>Elsie</span>
</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, 'lxml')
print(soup.a.parent)
print(type(soup.a.parent)) # 父节点为 标签类
print(type(soup.a.parents)) # 祖先节点为 迭代器
for i, pars in enumerate(soup.a.parents):
print(i, pars)
print(list(enumerate(soup.a.parents))) # list 输出
#%% 获取兄弟并列的节点
# .next_siblings 下一个兄弟节点
# .previous_siblings 前一个兄弟界节点
html = """
<html>
<head>
<title>The Dormouse's story</title>
</head>
<body>
<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">
<span>Elsie</span>
</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, 'lxml')
print(soup.a.next_siblings) # 迭代器的类型的返回
print(list(enumerate(soup.a.next_siblings)))
print(list(enumerate(soup.a.previous_siblings)))
"""
以上的选择方式为表标签的选择方式，方式快，但是满足不够
"""
#%% 标准选择器 find_all 根据标签名， 属性，选择标签 列表返回
# find_all (name, attrs, recursiv, text, **kwargs)
#%% 标签名选择 name
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
print(soup.find_all('ul'))
print(type(soup.find_all('ul')))
print(soup.find_all('ul')[0])
#%% 循环嵌套 find_all
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
for ul in soup.find_all('ul'):
print(soup.find_all('li')) # 循环嵌套的方式查找 ul 标签中的li标签
#%% attrs 属性查找对应的内容
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1" name="elements">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
print(soup.find_all(attrs={'id':'list-1'})) # 匹配所有符合该 属性的标签内容
print(soup.find_all(attrs={'name':'elements'})) # 两次的匹配结果实际上一致
## 更简单的写法
print(soup.find_all(id='list-1'))
print(soup.find_all(class_= 'list')) # 再这个地方class 为关键字， 因此加下划线来进行区分
#%% 使用文本的内容进行匹配 text
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
print(soup.find_all(text='Foo')) # 有两处满足 输出文本， 不输出完整的标签
#%% find 方法 只返回单个匹配的元素， 不返回所有的结果
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
print(soup.find('ul')) # 值返回第一个匹配的结果
#%% 其他选择， 类似于标签的选择
"""
### find_parents() find_parent()
find_parents()返回所有祖先节点，find_parent()返回直接父节点。
### find_next_siblings() find_next_sibling()
### find_previous_siblings() find_previous_sibling()
find_previous_siblings()返回前面所有兄弟节点，find_previous_sibling()返回前面第一个兄弟节点。
### find_all_next() find_next()
find_all_next()返回节点后所有符合条件的节点, find_next()返回第一个符合条件的节点
### find_all_previous() 和 find_previous()
find_all_previous()返回节点后所有符合条件的节点, find_previous()返回第一个符合条件的节点
"""
#%% CSS 选择器 通过select 直接传入CSS选择器 就可以完成标签或者元素的的选择
# . 代表 class
# # 代表 id
# 空格 代表嵌套
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
print(soup.select('.panel .panel-heading')) # . 选择class
print(soup.select('.panel .panel-body'))
print(soup.select('ul li'))
print(type(soup.select('ul li'))) # 嵌套使用空格进行选择 选择后的对象为list
print(list(enumerate(soup.select('ul li'))))
print(list(soup.select('ul li')))
print(soup.select('#list-2')) # 通过 # 选择id 选出所有 id 符合条件的标签
print(soup.select('#list-1 .element')) # 通过 # id 选择 然后嵌套选出 class 为element的标签
#%% for嵌套选择
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
for ul in soup.select('ul'):
print(soup.select('li')) # 通过for循环嵌套选出 li 标签
print(soup.select('ul li')) # 使用空格 具有同等效果的嵌套
#%% select 获取标签的属性 [ ]
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
for ul in soup.select('ul'):
print(ul['class'])
print(ul.attrs['id']) # 使用 [ ] 的这两种方式都可以获取 标签的 id
#%% get_text 获取标签标签中的内容
html='''
<div class="panel">
<div class="panel-heading">
<h4>Hello</h4>
</div>
<div class="panel-body">
<ul class="list" ok hah id="list-1">
<li class="element">Foo</li>
<li class="element">Bar</li>
<li class="element">Jay</li>
</ul>
<ul class="list list-small" id="list-2">
<li class="element">Foo</li>
<li class="element">Bar</li>
</ul>
</div>
</div>
'''
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'lxml')
for li in soup.select('li'):
print(li.get_text('.title'))
#%% 示例
import requests
from bs4 import BeautifulSoup
html = requests.get('https://book.douban.com').text
#print(html.text)
soup = BeautifulSoup(html, 'lxml')
# print(soup.prettify())
for title in soup.select('.title '):
#print(soup.select('a'))
for a in soup.select('a'):
print(a['href'])
print(a.get_text())