xpath解析基础

#!/usr/bin/python

from lxml import etree 

if __name__ == "__main__":
    #实例化一个etree对象，且将被解析的源码加载到了该对象中
    tree = etree.parse('test.html')

    r = tree.xpath('./html/body/div')
    r = tree.xpath('./html//div')
    r = tree.xpath('//div')

    tree.xpath('//div[@class="song"]')
    tree.xpath('//div[@class="song"]/p[3]')
    tree.xpath('//div[@class="song"]//li[5]/a/text()')[0]
    tree.xpath('.//li[7]//text()')
    tree.xpath('//div[@class="song"]/img/@src')