XPath
表达式 | 描述 |
---|---|
nodename | 选取此节点的所有子节点 |
/ | 从根节点选取 |
//xxx | 从匹配选择的当前节点选择文档中的节点,而不考虑它们的位置 |
. | 选取当前节点 |
.. | 选取当前节点的父节点 |
@xxx | 选取属性内容 |
/text() | 选取文本内容 |
starts-with(@属性名称,属性字符相同部分) | 以相同字符开始 |
演示使用HTML内容
代码语言:javascript复制html = '''
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>测试-常规用法</title>
</head>
<body>
<div id="content">
<ul id="test1">
<li>这是第一条信息</li>
<li>这是第二条信息</li>
<li>这是第三条信息</li>
</ul>
<ul id="test2">
<li>这是第4条信息</li>
<li>这是第5条信息</li>
<li>这是第6条信息</li>
</ul>
<div id="url">
<a href="http://www.baidu.com">百度</a>
<a href="http://www.163.com" title="Netease">网易</a>
</div>
</div>
</body>
</html>
'''
lxml库
代码语言:javascript复制from lxml import etree
selector = etree.HTML()
content = selector.xpath()
/代表根节点开始的逐层获取
代码语言:javascript复制from lxml import etree
selector = etree.HTML(html)
content = selector.xpath('/html/head/title/text()')
print(content)
获取所有的li标签
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//li')
for c in content:
print(c)
获取所有title属性的值
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//@title')
for c in content:
print(c)
[]获取列表的index
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//ul[2]/li[1]/text()')
for c in content:
print(c)
# 这是第4条信息
获取所有的li的文本内容,无论在什么位置
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//li/text()')
for c in content:
print(c)
image.png
获取属性id=url的div下层的a标签所有href地址
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//div[@id="url"]/a/@href')
for c in content:
print(c)
获取属性class="test1"的ul下层的最后一个li标签的文本内容
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//ul[@class="test1"]/li[last()]/text()')
print(content)
获取所有含有id属性且值为test1的ul下层li的文字内容
代码语言:javascript复制selector = etree.HTML(html)
content = selector.xpath('//ul[@id="test1"]/li/text()')
for c in content:
print(c)
豆瓣读书250数据抓取
代码语言:javascript复制<table width="100%">
<tbody><tr class="item">
<td width="100" valign="top">
<a class="nbg" href="https://book.douban.com/subject/25862578/" onclick="moreurl(this,{i:'1'})">
<img src="https://img3.doubanio.com/view/subject/m/public/s27264181.jpg" width="90">
</a>
</td>
<td valign="top">
<div class="pl2">
<a href="https://book.douban.com/subject/25862578/" onclick=""moreurl(this,{i:'1'})"" title="解忧杂货店">
解忧杂货店
</a>
<br>
<span style="font-size:12px;">ナミヤ雑貨店の奇蹟</span>
</div>
<p class="pl">[日] 东野圭吾 / 李盈春 / 南海出版公司 / 2014-5 / 39.50元</p>
<div class="star clearfix">
<span class="allstar45"></span>
<span class="rating_nums">8.6</span>
<span class="pl">(
294790人评价
)</span>
</div>
<p class="quote" style="margin: 10px 0; color: #666">
<span class="inq">一碗精心熬制的东野牌鸡汤,拒绝很难</span>
</p>
</td>
</tr>
</tbody></table>
image.png
代码语言:javascript复制import requests
from lxml import etree
headers={
'Accept':'*/*',
'Accept-Encoding':'gzip, deflate',
'Accept-Language':'zh-CN,zh;q=0.8',
'Connection':'keep-alive',
'Origin':'https://book.douban.com',
'Referer':'https://book.douban.com/',
'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.221 Safari/537.36 SE 2.X MetaSr 1.0'
}
for i in range(0, 10):
url = 'https://book.douban.com/top250?start={}'.format(i * 25)
html = requests.get(url, headers=headers).content
sel = etree.HTML(html)
tables = sel.xpath('//div[@class="indent"]/table')
for table in tables:
item = table.xpath('tr[@class="item"]/td[@valign="top"][2]')
print(item[0].xpath('div[@class="pl2"]/a/@title')[0])
print(item[0].xpath('p[@class="pl"]/text()')[0])
quote = item[0].xpath('p[@class="quote"]/span/text()')
if quote:
print([0])