轻轻学爬虫—scrapy框架巧用6—猴子偷桃（2）
作者：互联网
# 轻轻学爬虫—scrapy框架巧用6—猴子偷桃（2）
上节课我们讲解了bs4的一部分使用方法，今天我们来继续学习。我们还是以上节课的数据为例子
```python
html_doc = """
The Dormouse's story
<body>
The Dormouse's story
<body>
The Dormouse's story
Once upon a time there were three little sisters; and their names were Elsie, Lacie and Tillie; and they lived at the bottom of a well.
...
""" from bs4 import BeautifulSoup soup = BeautifulSoup(html_doc, 'html.parser') soup.prettify() print(soup) #得到下面结构化的html ""“The Dormouse's story
Once upon a time there were three little sisters; and their names were Elsie , Lacie and Tillie ; and they lived at the bottom of a well.
...
""" ``` ## Attributes 一个tag可能有很多个属性，tag `` 有一个 “class” 的属性,值为 “sister” . tag的属性的操作方法与字典相同: ```python from bs4 import BeautifulSoup soup = BeautifulSoup(html_doc, 'html.parser') soup.prettify() #获取属性 tag = soup.a print(tag['class']) #也可以这样写 print(soup.a['class']) #打印输出 ['sister'] ``` 也可以直接取属性, 比如: `.attrs` : ```python # 获取属性 print(tag.attrs) # 打印输出得到 {'href': 'http://example.com/elsie', 'class': ['sister'], 'id': 'link1'} ``` ## .contents 和 .children tag的 `.contents` 属性可以将tag的子节点以列表的方式输出: ```python p_tag = soup.p print(p_tag.contents) #打印输出 [The Dormouse's story] ``` 通过tag的 `.children` 生成器,可以对tag的子节点进行循环: ```python for child in p_tag.children: print(child) #打印输出 The Dormouse's story ``` ## .descendants `.descendants` 属性可以对所有tag的子孙节点进行递归循环 ```python for i in p_tag.descendants: print(i) # 打印输出 The Dormouse's story ``` ## .string 如果tag只有一个 `NavigableString` 类型子节点,那么这个tag可以使用 `.string` 得到子节点内容: ```python for child in p_tag.children: print(child.string) #打印输出 The Dormouse's story ``` ## .strings 和 stripped_strings 如果tag中包含多个字符串，可以使用 `.strings` 来循环获取: ``` for string in soup.strings: print(string) # 打印输出结果 The Dormouse's story The Dormouse's story Once upon a time there were three little sisters; and their names were Elsie , Lacie and Tillie ; and they lived at the bottom of a well. ... ``` 输出的字符串中可能包含了很多空格或空行,使用 `.stripped_strings` 可以去除多余空白内容: ```python for string in soup.stripped_strings: print(string) # 输出结果 The Dormouse's story The Dormouse's story Once upon a time there were three little sisters; and their names were Elsie , Lacie and Tillie ; and they lived at the bottom of a well. ... ``` 本节内容不少了小伙伴们先消化一下，后续知识还不少，一点点学习。 码字不易，欢迎大家在评论区留言，收藏。或者加入[群聊](https://jq.qq.com/?_wv=1027&k=vH00muGu)一起进步学习。