#PyQuery
强大又灵活的网页解析库
初始化
字符串初始化
html = """
<div class="box">
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
</ul>
</div>
<div class="container">
<p>这是一段文字</p>
<span>很酷！</span>
</div>
"""
from pyquery import PyQuery as pq
doc = pq(html)
print(doc('li'))
#打印所有的li标签
注释
首先引入PyQuery对象 取名pq。将HTML字符串当作参数传递给PyQuery类，就完成了初始化
URL初始化
from pyquery import PyQuery as pq
doc = pq(url="http://www.itaolaity.com")
print(doc('title'))
>>> <title>Tashi-丛林深处有书和黄金屋</title>
文件初始化
from pyquery import PyQuery as pq
doc = pq(filename='Demo.html')
print(doc('title'))
CSS选择器
基本用法
html = """
<div class="box">
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
</ul>
</div>
<div class="container">
<p>这是一段文字</p>
<span>很酷！</span>
</div>
"""
from pyquery import PyQuery as pq
doc = pq(html)
print(doc(".box li")) # 选取CLSS为box的节点 然后再选取内部的li节点
查找结点
- 子节点
find() 查找范围是节点的所有子孙节点
children() 方法查找子节点
html = """
<div class="box">
<div class="init1"></div>
<div class="init2">
<p>Tashi</p>
<h1>丛林深处有书和黄金屋</h1>
</div>
<div class="init3"></div>
</div>
"""
from pyquery import PyQuery as pq
doc = pq(html) # 初始化操作
# print(doc('.box'))
# print(type(doc('.box'))) # <class 'pyquery.pyquery.PyQuery'>
f = doc('.box')
s = f.find('.init2')
print(s)
## 注释 先找到父节点box 然后通过父节点的find()方法 找子节点为class="init2"的
html = """
<div class="box">
<div class="init1"></div>
<div class="init2">
<p>Tashi</p>
<h1 id="sign">丛林深处有书和黄金屋</h1>
</div>
<div class="init3"></div>
</div>
"""
from pyquery import PyQuery as pq
doc = pq(html)
f = doc('.box')
s = f.find('#sign') # 子孙节点都可以找到
s = f.children('#sign') # 找不到 只可以寻找子节点
print(s)
- 父节点
parent() 父节点
parents() 祖先节点
- 兄弟节点
siblings()
遍历
html = """
<div class="box">
<ul class="nav1">
<li><a href="#">百度</a></li>
<li><a href="#">淘宝</a></li>
<li><a href="#">丘比特</a></li>
<li><a href="#">Python</a></li>
<li><a href="#">Tashi</a></li>
</ul>
<ul class="nav2">
<ol>
<li>Gulu</li>
<li>Heng</li>
</ol>
</ul>
</div>
"""
from pyquery import PyQuery as pq
doc = pq(html)
lis = doc('li')
print(type(lis))
print(lis)
lis = doc('li').items()
print(type(lis))
for li in lis:
print(li)
获取信息
获取属性
.attr(‘属性值’)
获取文本
.text()
节点操作
增加节点和移除节点
addClass()
removeClass()
tml = """
<div class="box1"></div>
<div class="box2"></div>
"""
from pyquery import PyQuery as pq
doc = pq(html) # 初始化
box = doc('div')
print(box)
box.addClass('haha') ###
print(box)
box.removeClass('box1') ###
print(box)
html = """
<section></section>
"""
from pyquery import PyQuery as pq
doc = pq(html) # 初始化
art = doc('section')
print(art) # 寻找
art.attr('class', 'artO')
print(art) # 增加一个class
art.text('这是一个文章')
print(art)
art.html("<span>真酷</span>")
print(art)
伪类选择器
html = """
<div class="box">
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
<li>5</li>
</ul>
</div>
"""
from pyquery import PyQuery as pq
doc = pq(html) #初始化
li = doc('li:first-child')
print(li)
li = doc('li:last-child')
print(li)
li = doc('li:nth-child(3)')
print(li)
