python爬虫---从零开始（五）pyQuery库

 

什么是pyQuery：

　　强大又灵活的网页解析库。如果你觉得正则写起来太麻烦（我不会写正则），如果你觉得BeautifulSoup的语法太难记，如果你熟悉JQuery的语法，那么PyQuery就是你最佳的选择。

pyQuery的安装pip3 install pyquery即可安装啦。

pyQuery的基本用法：

初始化：

字符串初始化：

#!/usr/bin/env python
# -*- coding: utf-8 -*-

html = """

    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('#link1')
print(items)
print(items.parents('body'))

运行结果：

兄弟元素：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 兄弟元素

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('#link1')
print(items)
print(items.siblings('#link2'))

运行结果：

上面就把查找元素的方法都说了，下面我来看一下如何遍历元素。

遍历

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 兄弟元素

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('a')
for k,v in enumerate(items.items()):
    print(k,v)

运行结果：

 获取信息：

　　获取属性：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 获取属性

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('a')
print(items)
print(items.attr('href'))
print(items.attr.href)

运行结果：

　　获得文本：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 获取属性

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('a')
print(items)
print(items.text())
print(type(items.text()))

运行结果：

　　获得HTML：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 获取属性

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('a')
print(items.html())

运行结果：

DOM操作：

addClass、removeClass

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# DOM操作，addClass、removeClass

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('#link2')
print(items)
items.addClass('addStyle') # add_class
print(items)
items.remove_class('sister') # removeClass 
print(items)

运行结果：

attr、css：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# DOM操作，attr,css

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('#link2')
items.attr('name','addname')
print(items)
items.css('width','100px')
print(items)

可以给予新的属性，如果原来有该属性，会覆盖掉原有的属性

运行结果：

remove：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# DOM操作，remove

html = """

    Hello World
    
This is a paragraph.

"""
from pyquery import PyQuery as pq
doc = pq(html)
wrap = doc('.wrap')
print(wrap.text())
wrap.find('p').remove()
print("remove以后的数据")
print(wrap)

运行结果：

还有很多其他的DOM方法，想了解更多的小伙伴可以阅读其官方文档，地址：https://pyquery.readthedocs.io/en/latest/api.html

伪类选择器：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# DOM操作，伪类选择器

html = """

    
        
    
    
        
Once upo a time were three little sister;and theru name were
            
                Elsie
            
            Lacie
            and 
            Title
            Title
        
        
...
"""
from pyquery import PyQuery as pq
doc = pq(html)
# print(doc)
wrap = doc('a:first-child') # 第一个标签
print(wrap)
wrap = doc('a:last-child')  # 最后一个标签
print(wrap)
wrap = doc('a:nth-child(2)') # 第二个标签
print(wrap)
wrap = doc('a:gt(2)') # 比2大的索引 标签  即为  0 1 2 3 4 从0开始的  不是1
print(wrap)
wrap = doc('a:nth-child(2n)') # 第 2的整数倍 个标签
print(wrap)
wrap = doc('a:contains(Lacie)') # 包含Lacie文本的标签
print(wrap)

这里不在详细的一一列举了，了解更多CSS选择器可以查看官方文档，由W3C提供地址：http://www.w3school.com.cn/css/index.asp

到这里我们就把pyQuery的使用方法大致的说完了，想了解更多，更详细的可以阅读官方文档，地址：https://pyquery.readthedocs.io/en/latest/

上述代码地址：https://gitee.com/dwyui/pyQuery.git

　　　　　　　　　　感谢大家的阅读，不正确的地方，还希望大家来斧正，鞠躬，谢谢。