beautifulsoup的一些使用

自动补全代码：

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
print(soup.prettify())#如果html代码补全，则自动补全
print(soup.title.string)

查找标签

#基本使用
soup.title#<title>xxxxxxx</title>
soup.title.string#xxxxxx

获取名称

#基本使用
soup.title#<title>xxxxxxx</title>
soup.title.name#title

获取属性

#基本使用
soup.a#<a>xxxxxxx</a>
soup.a['name']#a标签的name属性值

获取内容

soup.title.string#xxxxxx

---

嵌套选择

print(soup.head.title.string)

子节点

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
print(soup.div.contents)

或者

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.div.children
print(a)
for i,j in enumerate(a):
    print(i,j)

子孙节点

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.div.descendants
print(a)
for i,j in enumerate(a):
    print(i,j)

获取父节点

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.div.parent
print(a)

获取祖先节点

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.div.parents
for i,j in enumerate(a):
    print(i,j)

获取兄弟节点

a=soup.div.next_siblings#后面的兄弟节点（迭代器）

前面的兄弟节点

a=soup.div.next_siblings#前面的兄弟节点（迭代器）

---

标准选择器
find_all(name,attrs,recursive,**kwargs)

name

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
print(soup.find_all('ul'))#根据标签名查找

import requests
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
for ul in soup.find_all('ul'):
    for li in ul.find_all('li'):
        print(li)

attrs

import requests
import re
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.find_all(attrs={'class':'lazy'})#<a class='lazy'>xxxxx</lazy>
for index,i in enumerate(a):
    result=re.findall(r'[a-zA-z]+://[^\s]*png',str(i))
    url=result[0]
    res = requests.get(url)
    with open('%d.png'%index,'wb')as f:
        f.write(res.content)

import requests
import re
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
a=soup.find_all(class_='lazy')
a=soup.find_all(id='lazy')

CSS选择器

import requests
import re
from bs4 import BeautifulSoup
response=requests.get('https://www.ithome.com/html/it/340684.htm',timeout=9)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.select('.lazy')

for index,i in enumerate(a):
    result=re.findall(r'[a-zA-z]+://[^\s]*png',str(i))
    url=result[0]
    res = requests.get(url)
    with open('./test/%d.png'%(index+1),'wb')as f:
        f.write(res.content)

获取css属性

import requests
import re
from bs4 import BeautifulSoup
headers={
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.108 Safari/537.36"
}
response=requests.get('https://www.zhihu.com/question/20519068/answer/215288567',headers=headers,timeout=None)
result=response.text
soup=BeautifulSoup(response.content,'lxml')
# print(soup.prettify())
a=soup.select('.lazy')
# print(a)
for index,i in enumerate(a):
    url=i['data-original']
# 
　　 #result=re.findall(r'[a-zA-z]+://[^\s]*jpg',str(i))
    # url=result[0]
    res = requests.get(url)
    with open('./test/%d.jpg'%(index+1),'wb')as f:
        f.write(res.content)

获取内容

li.get_text()