> For the complete documentation index, see [llms.txt](https://moluo.gitbook.io/notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://moluo.gitbook.io/notes/bian-cheng-xue-xi/python/scrapy/4.6xpath-ji-chu-yu-fa.md).

# 4.6xpath基础语法

请参阅<https://www.runoob.com/xpath/xpath-syntax.html>

xpath用法 获取内容 /h2/text() 标签固定样式 //span\[@class='vote-post-up'] 标签包含某个样式 //span\[contains(@class=,'vote-post-up')]

## 如何在scrapy中使用xpath？

scrapy抓取到http源码之后，将抓取结果保存到response中，通过respense.xpath("{xpath 表达式}")即可过滤出想要的内容。

respense.xpath()返回一个`scrapy.selector.unified.SelectorList`对象

通过SelectorList的extract()可以返回一个unicode字符串列表

命令行方式：scrapy shell {待抓取的url}，示例如下

```bash
scrapy shell http://blog.jobbole.com

response.xpath(".entry-header h1")
response.xpath(".entry-header h1::text").extract()
response.xpath(".entry-header h1::text").extract()[0]
```

pycharm调试方式

debug模式下使用