我们打开东方财富网站：http://quote.eastmoney.com/stocklist.html

假如懒得爬，也可以用现成的股票数据源：https://stockapi.com.cn

这展示了所有股票信息，不过需要我们分页去爬取
我们可以查询具体的html代码：

<div class="stock-info" data-spm="2"><div class="stock-bets"><h1><a class="bets-name" href="/stock/sz300388.html">国祯环保 (<span>300388</span>)</a><span class="state f-up">已休市 2017-09-29  15:00:03</span></h1><div class="price s-stop "><strong  class="_close">--</strong><span>--</span><span>--</span></div><div class="bets-content"><div class="line1"><dl><dt>今开</dt><dd class="">19.92</dd></dl><dl><dt>成交量</dt><dd>8917手</dd></dl><dl><dt>最高</dt><dd class="s-up">20.15</dd></dl><dl><dt>涨停</dt><dd class="s-up">21.96</dd></dl><dl><dt>内盘</dt><dd>4974手</dd></dl><dl><dt>成交额</dt><dd>1786.10万</dd></dl><dl><dt>委比</dt><dd>-50.69%</dd></dl><dl><dt>流通市值</dt><dd>59.98亿</dd></dl><dl><dt class="mt-1">市盈率<sup>MRQ</sup></dt><dd>50.59</dd></dl><dl><dt>每股收益</dt><dd>0.20</dd></dl><dl><dt>总股本</dt><dd>3.06亿</dd></dl><div class="clear"></div></div><div class="line2"><dl><dt>昨收</dt><dd>19.96</dd></dl><dl><dt>换手率</dt><dd>0.30%</dd></dl><dl><dt>最低</dt><dd class="s-down">19.92</dd></dl><dl><dt>跌停</dt><dd class="s-down">17.96</dd></dl><dl><dt>外盘</dt><dd>3943手</dd></dl><dl><dt>振幅</dt><dd>1.15%</dd></dl><dl><dt>量比</dt><dd>0.11</dd></dl><dl><dt>总市值</dt><dd>61.35亿</dd></dl><dl><dt>市净率</dt><dd>3.91</dd></dl><dl><dt>每股净资产</dt><dd>5.14</dd></dl><dl><dt>流通股本</dt><dd>2.99亿</dd></dl></div><div class="clear"></div></div></div>

发现股票名称在class="bets-name"的a标签中，其他的数据都在dt和dd标签中

import requests
from bs4 import BeautifulSoup
import re#优化，可以减少程序判断编码所花费的时间
def getHTMLText(url, code='UTF-8'):try:r = requests.get(url)r.raise_for_status()r.encoding = codereturn r.textexcept:return ""def getStockList(url, stockList):html = getHTMLText(url, 'GB2312')soup = BeautifulSoup(html, 'html.parser')aInformaton = soup.find_all('a')for ainfo in aInformaton:try:stockList.append(re.findall(r'[s][hz]\d{6}', ainfo.attrs['href'])[0])except:continuedef getStockInformation(detailUrl, outputFile, stockList):count = 0for name in stockList:count = count + 1stockUrl = detailUrl + name + '.html'html = getHTMLText(stockUrl)try:if html == "":continuestockDict = {}soup = BeautifulSoup(html, 'html.parser')stockinfo = soup.find('div', attrs={'class': 'stock-bets'})stockname = stockinfo.find('a', attrs={'class': 'bets-name'})# 当标签内部还有标签时，利用text可以得到正确的文字，利用string可能会产生NonestockDict["股票名称"] = stockname.text.split()[0]stockKey = stockinfo.find_all('dt')stockValue = stockinfo.find_all('dd')for i in range(len(stockKey)):stockDict[stockKey[i].string] = stockValue[i].string#\r移动到行首，end=""不进行换行print("\r{:5.2f}%".format((count / len(stockList) * 100)), end='')#追加写模式'a'f = open(outputFile, 'a')f.write(str(stockDict) + '\n')f.close()except:print("{:5.2f}%".format((count / len(stockList) * 100)), end='')continuedef main():listUrl = 'http://quote.eastmoney.com/stocklist.html'detailUrl = 'https://gupiao.baidu.com/stock/'outputFile = 'C:/Users/Administrator/Desktop/out.txt'stockList = []getStockList(listUrl, stockList)getStockInformation(detailUrl, outputFile, stockList)
main()

方法2.采用Scrapy框架和正则表达式库
（1）建立工程和Spider模板（保存为stocks.py文件）
在命令行中进入：E:\PythonProject\BaiduStocks

输入：scrapy startproject BaiduStocks 建立了scrapy工程

输入：scrapy genspider stocks baidu.com 建立spider模板，baidu.com是指爬虫限定的爬取域名，在stocks.py文件删去即可

（2）编写spider爬虫（即stocks.py文件）
采用css选择器，可以返回选择的标签元素，通过方法extract()可以提取标签元素为字符串从而实现匹配正则表达式的处理

正则表达式详解：

<a class="bets-name" href="/stock/sz300388.html">国祯环保 (<span>300388</span>)</a>

re.findall(‘.(‘, stockname)[0].split()[0] + ‘(’+re.findall(’>.<’, stockname)[0][1:-1]+‘)’

匹配结果：国祯环保（300388）

因为’('为正则表达式语法里的基本符号，所以需要转义

正则表达式从每行开始匹配，匹配之后返回[’ 国祯环保 (']，采用split将空白字符分割，返回[‘国祯环保’，‘(’]

# -*- coding: utf-8 -*-
import scrapy
import reclass StocksSpider(scrapy.Spider):name = 'stocks'start_urls = ['http://quote.eastmoney.com/stocklist.html']def parse(self, response):fo=open(r'E:\PythonProject\BaiduStocks\oo.txt','a')#fo.write(str(response.css('a').extract()))count=0for href in response.css('a').extract():try:if count == 300:breakcount=count+1stockname=re.findall(r'[s][hz]\d{6}',href)[0]stockurl='https://gupiao.baidu.com/stock/' + stockname + '.html'#fo.write(stockurl)yield scrapy.Request(url= stockurl,headers={"User-Agent":"Chrome/10"} ,callback=self.stock_parse)except:continuepassdef stock_parse(self,response):ffo=open(r'E:\PythonProject\BaiduStocks\stockparse.txt','a')stockDict={}#提取标签中class="stock-bets"的标签元素stockinfo=response.css('.stock-bets')#将提取出来的标签转化为字符串列表，然后取第一个stockname=stockinfo.css('.bets-name').extract()[0]#ffo.write(stockname)keyList=stockinfo.css('dt').extract()#ffo.write(str(keyList))valueList=stockinfo.css('dd').extract()stockDict['股票名称'] = re.findall('.*\(', stockname)[0].split()[0] + '('+re.findall('\>.*\<', stockname)[0][1:-1]+')'for i in range(len(keyList)):stockkey=re.findall(r'>.*</dt>',keyList[i])[0][1:-5]stockvalue=re.findall(r'>.*</dd>',valueList[i])[0][1:-5]stockDict[stockkey]=stockvalueyield stockDict

（3）编写PipeLine（即pipelines.py文件）

系统自动生成了Item处理类BaiduStocksPipeline，我们不采用系统生成，新建一个BaiduStocksinfoPipeline类，并书写Item处理函数

# -*- coding: utf-8 -*-# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: http://doc.scrapy.org/en/latest/topics/item-pipeline.htmlclass BaidustocksPipeline(object):def process_item(self, item, spider):return itemclass BaidustocksinfoPipeline(object):#爬虫打开时执行def open_spider(self,spider):self.f=open(r'E:\PythonProject\BaiduStocks\BaiduStocks\asdqwe.txt','a')# 爬虫关闭时执行def close_spider(self,spider):self.f.close()#处理Item项def process_item(self,item,spider):try:self.f.write(str(item)+'\n')except:passreturn item

此时要修改配置文件setting.py文件

ITEM_PIPELINES = {'BaiduStocks.pipelines.BaidustocksinfoPipeline': 300,
}

（4）运行爬虫：scrapy crawl stocks