如何使用 Python 2 从网站上抓取数据？

Question

So when I run this code I keep getting empty brackets instead of the actual data.

I am trying to figure out why sense I don't receive any error messages.

import urllib
import re
symbolslist = ["aapl","spy","goog","nflx"]


for symbol in symbolslist:
    url = "http://finance.yahoo.com/q?s=%s&ql=1"%(symbol)
    htmlfile = urllib.urlopen(url)
    htmltext = htmlfile.read()
    regex = '<span id="yfs_184_%s">(.+?)</span>'%(symbol.lower())
    pattern = re.compile(regex)
    price = re.findall(pattern, htmltext)
    print price

Answer 1

括号出现是因为正则表达式的元素代码不是 184 它的 l84 它的 L 不是一个。

Answer 2

There is a number of libraries around which can help you to scrape sites. Take a look at Scrapy or at Beautiful Soup they should support both Python 2 and 3 as far as I know.