Spider-PyQuery基本用法
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pip install pyquery
2.引用方法
from pyquery import PyQuery as pq
3.简介
pyquery 是类型jquery 的一个专供python使用的html解析的库，使用方法类似bs4。
4.使用方法
4.1 初始化方法：
from pyquery import PyQuery as pq
doc =pq(html) #解析html字符串
doc =pq("http://news.baidu.com/") #解析网页
doc =pq("./a.html") #解析html 文本
4.2 基本CSS选择器
from pyquery import PyQuery as pq
html = ‘‘‘
<div id="wrap">
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
print doc("#wrap .s_from link")
运行结果：
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
#是查找id的标签 .是查找class 的标签 link 是查找link 标签 中间的空格表示里层
4.3 查找子元素
from pyquery import PyQuery as pq
html = ‘‘‘
<div id="wrap">
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
#查找子元素
doc = pq(html)
items=doc("#wrap")
print(items)
print("类型为:%s"%type(items))
link = items.find(‘.s_from‘)
print(link)
link = items.children()
print(link)
运行结果：
<div id="wrap">
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
类型为:<class ‘pyquery.pyquery.PyQuery‘>
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
根据运行结果可以发现返回结果类型为pyquery，并且find方法和children 方法都可以获取里层标签
4.4查找父元素
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
items=doc(".s_from")
print(items)
#查找父元素
parent_href=items.parent()
print(parent_href)
运行结果:
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link href="http://asda.com">asdadasdad12312</link>
<link href="http://asda1.com">asdadasdad12312</link>
<link href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
parent可以查找出外层标签包括的内容，与之类似的还有parents,可以获取所有外层节点
4.5 查找兄弟元素
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com">asdadasdad12312</link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
items=doc("link.active1.a123")
print(items)
#查找兄弟元素
siblings_href=items.siblings()
print(siblings_href)
运行结果：
<link class="active1 a123" href="http://asda.com">asdadasdad12312</link>
<link class="active2" href="http://asda1.com">asdadasdad12312</link>
<link class="movie1" href="http://asda2.com">asdadasdad12312</link>
根据运行结果可以看出，siblings 返回了同级的其他标签
结论：子元素查找，父元素查找，兄弟元素查找，这些方法返回的结果类型都是pyquery类型，可以针对结果再次进行选择
4.6 遍历查找结果
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com">asdadasdad12312</link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link").items()
for it in its:
print(it)
运行结果：
<link class="active1 a123" href="http://asda.com">asdadasdad12312</link>
<link class="active2" href="http://asda1.com">asdadasdad12312</link>
<link class="movie1" href="http://asda2.com">asdadasdad12312</link>
4.7获取属性信息
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com">asdadasdad12312</link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link").items()
for it in its:
print(it.attr(‘href‘))
print(it.attr.href)
运行结果：
http://asda.com http://asda.com http://asda1.com http://asda1.com http://asda2.com http://asda2.com
4.8 获取文本
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com">asdadasdad12312</link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link").items()
for it in its:
print(it.text())
运行结果
asdadasdad12312 asdadasdad12312 asdadasdad12312
4.9 获取 HTML信息
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com"><a>asdadasdad12312</a></link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link").items()
for it in its:
print(it.html())
运行结果：
<a>asdadasdad12312</a> asdadasdad12312 asdadasdad12312
5.常用DOM操作
5.1 addClass removeClass
添加，移除class标签
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com"><a>asdadasdad12312</a></link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link").items()
for it in its:
print("添加:%s"%it.addClass(‘active1‘))
print("移除:%s"%it.removeClass(‘active1‘))
运行结果
添加:<link class="active1 a123" href="http://asda.com"><a>asdadasdad12312</a></link>
移除:<link class="a123" href="http://asda.com"><a>asdadasdad12312</a></link>
添加:<link class="active2 active1" href="http://asda1.com">asdadasdad12312</link>
移除:<link class="active2" href="http://asda1.com">asdadasdad12312</link>
添加:<link class="movie1 active1" href="http://asda2.com">asdadasdad12312</link>
移除:<link class="movie1" href="http://asda2.com">asdadasdad12312</link>
需要注意的是已经存在的class标签不会继续添加
5.2 attr css
attr 为获取/修改属性 css 添加style属性
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com"><a>asdadasdad12312</a></link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link").items()
for it in its:
print("修改:%s"%it.attr(‘class‘,‘active‘))
print("添加:%s"%it.css(‘font-size‘,‘14px‘))
运行结果
C:Python27python.exe D:/test_his/test_re_1.py
修改:<link class="active" href="http://asda.com"><a>asdadasdad12312</a></link>
添加:<link class="active" href="http://asda.com" style="font-size: 14px"><a>asdadasdad12312</a></link>
修改:<link class="active" href="http://asda1.com">asdadasdad12312</link>
添加:<link class="active" href="http://asda1.com" style="font-size: 14px">asdadasdad12312</link>
修改:<link class="active" href="http://asda2.com">asdadasdad12312</link>
添加:<link class="active" href="http://asda2.com" style="font-size: 14px">asdadasdad12312</link>
attr css操作直接修改对象的
5.3 remove
remove 移除标签
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com"><a>asdadasdad12312</a></link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("div")
print(‘移除前获取文本结果:
%s‘%its.text())
it=its.remove(‘ul‘)
print(‘移除后获取文本结果:
%s‘%it.text())
运行结果
移除前获取文本结果: hello nihao asdasd asdadasdad12312 asdadasdad12312 asdadasdad12312 移除后获取文本结果: hello nihao
其他DOM方法参考： 请点击
6.伪类选择器
from pyquery import PyQuery as pq
html = ‘‘‘
<div href="wrap">
hello nihao
<ul class="s_from">
asdasd
<link class=‘active1 a123‘ href="http://asda.com"><a>helloasdadasdad12312</a></link>
<link class=‘active2‘ href="http://asda1.com">asdadasdad12312</link>
<link class=‘movie1‘ href="http://asda2.com">asdadasdad12312</link>
</ul>
</div>
‘‘‘
doc = pq(html)
its=doc("link:first-child")
print(‘第一个标签:%s‘%its)
its=doc("link:last-child")
print(‘最后一个标签:%s‘%its)
its=doc("link:nth-child(2)")
print(‘第二个标签:%s‘%its)
its=doc("link:gt(0)") #从零开始
print("获取0以后的标签:%s"%its)
its=doc("link:nth-child(2n-1)")
print("获取奇数标签:%s"%its)
its=doc("link:contains(‘hello‘)")
print("获取文本包含hello的标签:%s"%its)
运行结果
第一个标签:<link class="active1 a123" href="http://asda.com"><a>helloasdadasdad12312</a></link>
最后一个标签:<link class="movie1" href="http://asda2.com">asdadasdad12312</link>
第二个标签:<link class="active2" href="http://asda1.com">asdadasdad12312</link>
获取0以后的标签:<link class="active2" href="http://asda1.com">asdadasdad12312</link>
<link class="movie1" href="http://asda2.com">asdadasdad12312</link>
获取奇数标签:<link class="active1 a123" href="http://asda.com"><a>helloasdadasdad12312</a></link>
<link class="movie1" href="http://asda2.com">asdadasdad12312</link>
获取文本包含hello的标签:<link class="active1 a123" href="http://asda.com"><a>helloasdadasdad12312</a></link>
更多css选择器可以查看： 请点击
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