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老师我按你的步骤，pip3分别安装了bs4和lxml；一直报这个错误 File "D:\python\lib\site-packages\bs4\__init__.py", line 228, in __init__ % ",".join(features)) bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

Beautiful Soup对文档的解析速度不会比它所依赖的解析器更快,如果对计算时间要求很高或者计算机的时间比程序员的时间更值钱,那么就应该直接使用 lxml .

老师。只用lxml，不用bs4也好用的。 page = requests.get（） tree = html.fromstring(page.text)

老师，lxml和bs4的适用场景有啥区别。感觉这两个都可以解析html文本

SyntaxError: Non-UTF-8 code starting with '\xcf' in file /usr/local/bin/python3.7 on line 1, but no encoding declared; 在pycharm上执行一直提示这个，看了官方文档，第一行代码也增加了coding=gbk等所有的方式，但还是不行，命令行下可以正常执行，为什么呢？

bs4可以实现urllib和requests的功能吧，是的话只调用bs4模块是否效率更高？

老师请问一下你那个html_doc咋导入的

from bs4 import BeautifulSoup import requests headers = { "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8", "Accept-Language": "zh-CN,zh;q=0.8", "Connection": "close", "Cookie": "_gauges_unique_hour=1; _gauges_unique_day=1; _gauges_unique_month=1; _gauges_unique_year=1; _gauges_unique=1", "Referer": "http://www.infoq.com", "Upgrade-Insecure-Requests": "1", "User-Agent": "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.98 Safari/537.36 LBBROWSER" } #url = 'http://www.infoq.com/cn/news' url = 'http://news.baidu.com/' def craw(url): response = requests.get(url, headers=headers) soup = BeautifulSoup(response.text, 'lxml') for hotnews in soup.find_all('div', class_='hotnews'): for news in hotnews.find_all('a'): print(news.text,end=' ') print(news.get('href')) craw(url) 换了个网页爬爬

print(soup.p['class']) 为什么匹配的是第一个title 而不是story

pip3安装bs4报错 之前安装requests都可以的 报错信息如下 07Exception: Traceback (most recent call last): File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\site-package s\pip\_vendor\urllib3\response.py", line 331, in _error_catcher yield File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\site-package s\pip\_vendor\urllib3\response.py", line 413, in read data = self._fp.read(amt) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\site-package s\pip\_vendor\cachecontrol\filewrapper.py", line 62, in read data = self.__fp.read(amt) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\http\client. py", line 449, in read n = self.readinto(b) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\http\client. py", line 493, in readinto n = self.fp.readinto(b) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\socket.py", line 586, in readinto return self._sock.recv_into(b) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\ssl.py", lin e 1009, in recv_into return self.read(nbytes, buffer) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\ssl.py", lin e 871, in read return self._sslobj.read(len, buffer) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\ssl.py", lin e 631, in read v = self._sslobj.read(len, buffer) socket.timeout: The read operation timed out During handling of the above exception, another exception occurred: Traceback (most recent call last): File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\site-package s\pip\_internal\cli\base_command.py", line 143, in main status = self.run(options, args) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\site-package s\pip\_internal\commands\install.py", line 318, in run resolver.resolve(requirement_set) File "c:\users\acadsoc\appdata\local\programs\python\python36\lib\site-package