| 解析器 | 使用方法 | 条件 |
| bs4的HTML解析器 | BeautifulSoup(mk,'html.parser') | 安装bs库 |
| lxml的HTML解析器 | BeautifulSoup(mk,'lxml') | pip install lxml |
| lxml的xml解析器 | BeautifulSoup(mk,'xml') | pip install lxml |
| html5lib的解析器 | BeautifulSoup(mk,'html5lib') | pip install html5lib |
| Tag | 标签，最基本的信息组织单元，分别用<>和</>标明开头和结尾 |
| Name | 标签的名字，<p></p>的名字是'p',格式:<tag>.name |
| Attributes | 标签的属性，字典形式组织，格式：<tag>.attrs |
| NavigableString | 标签内非属性字符串，<>...</>中字符串，格式：<tag>.string |
| comment | 标签内字符串的注释部分，一种特殊的comment（注释）类型 |
示例：
# url = 'http://python123.io/ws/demo.html' 网页HTML代码如下：
<html><head><title>This is a python demo page</title></head> <body> <p class="title"><b>The demo python introduces several python courses.</b></p> <p class="course">Python is a wonderful general-purpose programming language. You can learn Python from novice to professional by tracking the following courses: <a href="http://www.icourse163.org/course/BIT-268001" class="py1" id="link1">Basic Python</a> and <a href="http://www.icourse163.org/course/BIT-1001870001" class="py2" id="link2">Advanced Python</a>.</p> </body></html>
a标签的名字:
from bs4 import BeautifulSoup import requests url = 'http://python123.io/ws/demo.html' demo = requests.get(url) html = demo.text soup = BeautifulSoup(html,'html.parser') tag = soup.a print(tag.name)
运行结果：
a
a标签的父亲标签名字：
from bs4 import BeautifulSoup import requests url = 'http://python123.io/ws/demo.html' demo = requests.get(url) html = demo.text soup = BeautifulSoup(html,'html.parser') tag = soup.a.parent print(tag.name)
运行结果:
p
a标签的属性：
from bs4 import BeautifulSoup import requests url = 'http://python123.io/ws/demo.html' demo = requests.get(url) html = demo.text soup = BeautifulSoup(html,'html.parser') tag = soup.a print(tag.attrs) # 打印a标签的属性，得到字典
print(tag.attrs['class']) # 打印a标签的class属性值
print(tag.attrs['href']) # 打印a标签的href属性值
print(type(tag.attrs)) # 打印a标签属性类型
print(type(tag])) # 打印标签类型
print(tag.string) # 打印a标签的string
运行结果：
{'href': 'http://www.icourse163.org/course/BIT-268001', 'class': ['py1'], 'id': 'link1'}
['py1']
['http://www.icourse163.org/course/BIT-268001']
<class 'dict'>
<class 'bs4.element.Tag'>
Basic Python
| 属性 | 说明 |
| .contents | 子节点的列表，将<tag>所有儿子节点存入列表 |
| .children | 子节点的迭代类型，与.contents类似，用于循环遍历儿子节点 |
| .descendants | 子孙节点的迭代类型，包含所有子孙节点，用于遍历循环 |
示例：
from bs4 import BeautifulSoup import requests url = 'http://python123.io/ws/demo.html' demo = requests.get(url) html = demo.text soup = BeautifulSoup(html,'html.parser') print(soup.head) # 获取head标签节点 print('') print(soup.head.contents) # 获取head的所有节点 print('') print(soup.body.contents) # 获取body的所有节点 print('') print(str(len(soup.body.contents))) # 获取body的所有节点数量 print('') print(soup.body.contents[1]) # 获取body标签中的第2个节点
运行结果：
<head><title>This is a python demo page</title></head>
[<title>This is a python demo page</title>]
['
', <p class="title"><b>The demo python introduces several python courses.</b></p>, '
', <p class="course">Python is a wonderful general-purpose programming language. You can learn Python from novice to professional by tracking the following courses:
<a class="py1" href="http://www.icourse163.org/course/BIT-268001" id="link1">Basic Python</a> and <a class="py2" href="http://www.icourse163.org/course/BIT-1001870001" id="link2">Advanced Python</a>.</p>, '
']
5
<p class="title"><b>The demo python introduces several python courses.</b></p>
for child in soup.body.children: print(child) |
遍历儿子节点 |
for child in soup.body.descendants: print(child) |
遍历子孙节点 |
| .parent | 节点的父亲标签 |
| .parents | 节点的先辈标签的迭代类型，用于循环先辈节点 |
from bs4 import BeautifulSoup import requests url = 'http://python123.io/ws/demo.html' demo = requests.get(url) html = demo.text soup = BeautifulSoup(html,'html.parser')
''' 标签树上行遍历''' for parent in soup.a.parents: if parent is None: print(parent) else: print(parent.name) 运行结果： p body html [document]
| 属性 | 说明 |
| .next_sibling | 返回按照HTML文本顺序的下一个平行节点标签 |
| .previous_sibling | 返回按照HTML文本舒徐的上一个平行节点标签 |
| .next_siblings | 迭代类型，返回按照HTML文本顺序的后续所有平行节点标签 |
| .previous_siblings | 迭代类型，返回按照HTML文本顺序的前续所有平行节点标签 |
for sibling in next_siblings: print(siblink) |
遍历后续节点 |
for sibling in previous_siblings: print(siblink) |
遍历前续节点 |
from bs4 import BeautifulSoup import requests url = 'https://python123.io/ws/demo.html' r = requests.get(url) getHTML = r.text soup = BeautifulSoup(getHTML,"html.parser") print(soup.prettify())
D:python_workvenvScriptspython.exe D:/python_work/test.py <html> <head> <title> This is a python demo page </title> </head> <body> <p class="title"> <b> The demo python introduces several python courses. </b> </p> <p class="course"> Python is a wonderful general-purpose programming language. You can learn Python from novice to professional by tracking the following courses: <a class="py1" href="http://www.icourse163.org/course/BIT-268001" id="link1"> Basic Python </a> and <a class="py2" href="http://www.icourse163.org/course/BIT-1001870001" id="link2"> Advanced Python </a> . </p> </body> </html> Process finished with exit code 0
from bs4 import BeautifulSoup import requests url = 'https://python123.io/ws/demo.html' r = requests.get(url) getHTML = r.text soup = BeautifulSoup(getHTML,"html.parser") # 提取a标签的属性href的值 for link in soup.find_all('a'): print(link.get('href')) 运行结果： D:python_workvenvScriptspython.exe D:/python_work/test.py http://www.icourse163.org/course/BIT-268001 http://www.icourse163.org/course/BIT-1001870001 Process finished with exit code 0