pyquery 学习

　　pyquery 是python仿照jQuery的严格实现,语法与jQuery几乎完全相同,所以对于学过前端的朋友们可以立马上手,没学过的小朋友也别灰心,我们马上就能了解到pyquery的强大.

1 安装

  pip install pyquery

 

2 官方文档

http://pyquery.readthedocs.io/

 

3 学习代码html代码

  html = '''
  

      

           
first item
           
second item
           
third item
           
fourth item
           
fifth item
       
   
  '''

 

 

4 字符串初始化

html = '''

    

         
first item
         
second item
         
third item
         
fourth item
         
fifth item
     
 
'''
from pyquery import PyQuery as pq
# 格式化html文本,获取'$对象
doc=pq(html) # doc ---> '$'
#获取html文本下所有的li标签
print(doc('li'))

 

结果

 

5 URL初始化

from pyquery import PyQuery as pq
#直接获取网页源码
doc=pq(url='https://www.baidu.com')
title=doc(':submit').attr.value
print(title)

结果

 

6 文件初始化

from pyquery import PyQuery as pq
#读取文件
doc = pq(filename='demo.html') 
print(doc('li'))

 

结果

 

 

7 基于css选择器

html = '''

    

         
first item
         
second item
         
third item
         
fourth item
         
fifth item
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
#找id=container标签下 所有class=list标签下的 所有的li标签 
print(doc('#container .list li'))

 

结果

 

8 查找元素

子元素(不找孙子)

(链式寻找,doc($)找到的标签对象可以继续查找)

html = '''

    

         
first item
         
second item
         
third item
         
fourth item
         
fifth item
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
#先获取所有的class=list 标签
items = doc('.list')
#再获取所有的li标签
lis=items('li')
print(lis)

 

结果

#获取当前标签的所有子标签
lis=items.children()
print(type(lis))
print(lis)

 

结果

 

父元素(不找爷爷)

html = '''

    

        

             
first item
             
second item
             
third item
             
fourth item
             
fifth item
         
     

'''
from pyquery import PyQuery as pq
doc = pq(html)
items = doc('.list')
#获取当前标签的父级别标签(不取爷爷标签)
container = items.parent()
print(type(container))
print(container)

 

结果

 

 9 遍历

html = '''

    

        

             
first item
             
second item
             
third item
             
fourth item
             
fifth item
         
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
#寻找class=items-0并且class=active的标签
li = doc('.item-0.active')
print(li)

 

 结果

 

10 获取文本

html = '''

    

        

             
first item
             
second item
             
我们一起high high
             
fourth item
             
fifth item
         
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
#定位到 a标签
a = doc('.item-0.active a')
print(a)
#输出文本使用.text()
print(a.text())

 

结果

 

11 获取HTML

html = '''

    

        

             
first item
             
second item
             
third item
             
fourth item
             
fifth item
         
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
li = doc('.item-0.active')
print(li)
#获取对应 标签下的 html数据
print(li.html())

 

结果

 

12 DOM操作

addClass、removeClass

html = '''

    

        

             
first item
             
second item
             
third item
             
fourth item
             
fifth item
         
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
li = doc('.item-0.active')
print(li)
#给选定标签删除 class='active'
li.removeClass('active')
print(li)
#给选定标签添加 class='active'
li.addClass('active')
print(li)

 

结果

 

attr、css

html = '''

    

        

             
first item
             
second item
             
third item
             
fourth item
             
fifth item
         
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
li = doc('.item-0.active')
print(li)
#添加属性 name=link
li.attr('name', 'link')
print(li)
#添加css font-size=14px
li.css('font-size', '14px')
print(li)

 

结果

 

remove

html = '''

Hello, World
This is a paragraph.

'''
from pyquery import PyQuery as pq
doc = pq(html)
wrap = doc('.wrap')
print(wrap.text())
#find 找到指定标签,remove 移除
wrap.find('p').remove()
print(wrap.text())

 

结果

 

其他DOM方法

 

http://pyquery.readthedocs.io/en/latest/api.html

13 伪类选择器

html = '''

    

        

             
first item
             
second item
             
third item
             
fourth item
             
fifth item
         
     
 
'''
from pyquery import PyQuery as pq
doc = pq(html)
# 获取第一个li 标签
li = doc('li:first-child')
print(li)
#获取最后一个li 标签
li = doc('li:last-child')
print(li)
#获取第2个li 标签
li = doc('li:nth-child(2)')
print(li)
#获取索引>2 的li 标签
li = doc('li:gt(2)')
print(li)
#获取偶数 的li标签
li = doc('li:nth-child(2n)')
print(li)
#获取文本包含second的 li标签
li = doc('li:contains(second)')
print(li)

 

 结果

 

更多CSS选择器可以查看 http://www.w3school.com.cn/css/index.asp

 

转载于:https://www.cnblogs.com/angle6-liu/p/10698239.html