python 如何获取页面所有a标签下href的值

看代码吧~

# -*- coding:utf-8 -*-
#python 2.7
#http://tieba.baidu.com/p/2460150866
#标签操作 
 
from bs4 import BeautifulSoup
import urllib.request
import re 
 
#如果是网址，可以用这个办法来读取网页
#html_doc = \"http://tieba.baidu.com/p/2460150866\"
#req = urllib.request.Request(html_doc)  
#webpage = urllib.request.urlopen(req)  
#html = webpage.read() 
 
html=\"\"\"
<html><head><title>The Dormouse\'s story</title></head>
<body>
<p class=\"title\" name=\"dromouse\"><b>The Dormouse\'s story</b></p>
<p class=\"story\">Once upon a time there were three little sisters; and their names were
<a href=\"http://example.com/elsie\" rel=\"external nofollow\"  rel=\"external nofollow\"  class=\"sister\" id=\"xiaodeng\"><!-- Elsie --></a>,
<a href=\"http://example.com/lacie\" rel=\"external nofollow\"  rel=\"external nofollow\"  class=\"sister\" id=\"link2\">Lacie</a> and
<a href=\"http://example.com/tillie\" rel=\"external nofollow\"  class=\"sister\" id=\"link3\">Tillie</a>;
<a href=\"http://example.com/lacie\" rel=\"external nofollow\"  rel=\"external nofollow\"  class=\"sister\" id=\"xiaodeng\">Lacie</a>
and they lived at the bottom of a well.</p>
<p class=\"story\">...</p>
\"\"\"
soup = BeautifulSoup(html, \'html.parser\')   #文档对象 
 
#查找a标签,只会查找出一个a标签
#print(soup.a)#<a class=\"sister\" href=\"http://example.com/elsie\" rel=\"external nofollow\"  rel=\"external nofollow\"  id=\"xiaodeng\"><!-- Elsie --></a>
 
for k in soup.find_all(\'a\'):
    print(k)
    print(k[\'class\'])#查a标签的class属性
    print(k[\'id\'])#查a标签的id值
    print(k[\'href\'])#查a标签的href值
    print(k.string)#查a标签的string

如果，标签<a>中含有其他标签，比如<em>..</em>，此时要提取<a>中的数据，需要用k.get_text()

soup = BeautifulSoup(html, \'html.parser\')   #文档对象
#查找a标签,只会查找出一个a标签
for k in soup.find_all(\'a\'):
    print(k)
    print(k[\'class\'])#查a标签的class属性
    print(k[\'id\'])#查a标签的id值
    print(k[\'href\'])#查a标签的href值
    print(k.string)#查a标签的string

如果，标签<a>中含有其他标签，比如<em>..</em>，此时要提取<a>中的数据，需要用k.get_text()

通常我们使用下面这种模式也是能够处理的，下面的方法使用了get()。

 html = urlopen(url)
 soup = BeautifulSoup(html, \'html.parser\')
 t1 = soup.find_all(\'a\')
 print t1
 href_list = []
 for t2 in t1:
    t3 = t2.get(\'href\')
    href_list.append(t3)

补充：python爬虫获取任意页面的标签和属性（包括获取a标签的href属性）

看代码吧~

# coding=utf-8 
from bs4 import BeautifulSoup 
import requests 
# 定义一个获取url页面下label标签的attr属性的函数 
def getHtml(url, label, attr): 
    response = requests.get(url) 
    response.encoding = \'utf-8\' 
    html = response.text 
    soup = BeautifulSoup(html, \'html.parser\'); 
    for target in soup.find_all(label):
 
        try: 
            value = target.get(attr)
 
        except: 
            value = \'\'
 
        if value: 
            print(value)
 
url = \'https://baidu.com/\' 
label = \'a\' 
attr = \'href\' 
getHtml(url, label, attr)