爬虫四部曲：
1.从哪爬 where
2.爬什么 what
3.怎么爬 how
4.爬了之后信息如何保存 save

本文是练手程序之爬取三国演义

从哪爬

三国演义

爬什么

三国演义全文

怎么爬

在Chrome页面打开F12，就可以发现文章内容在节点

只要找到这个节点，然后把内容写入到一个html文件即可。

content = soup.find(\"div\", {\"class\": \"bookyuanjiao\", \"id\": \"con\"})

爬了之后如何保存

主要就是拿到内容，拼接到一个html文件，然后保存下来就可以了。

#!usr/bin/env  
# -*-coding:utf-8 -*-
import urllib2
import os
from bs4 import BeautifulSoup as BS
import locale
import sys
from lxml import etree
import re

reload(sys)
sys.setdefaultencoding(\'gbk\')

sub_folder = os.path.join(os.getcwd(), \"sanguoyanyi\")
if not os.path.exists(sub_folder):
    os.mkdir(sub_folder)

path = sub_folder

# customize html as head of the articles
input = open(r\'0.html\', \'r\')
head = input.read()

domain = \'http://www.shicimingju.com/book/sanguoyanyi.html\'
t = domain.find(r\'.html\')
new_domain = \'/\'.join(domain.split(\"/\")[:-2])
first_chapter_url = domain[:t] + \"/\" + str(1) + \'.html\'
print first_chapter_url

# Get url if chapter lists
req = urllib2.Request(url=domain)
resp = urllib2.urlopen(req)
html = resp.read()
soup = BS(html, \'lxml\')
chapter_list = soup.find(\"div\", {\"class\": \"bookyuanjiao\", \"id\": \"mulu\"})
sel = etree.HTML(str(chapter_list))
result = sel.xpath(\'//li/a/@href\')

for each_link in result:
    each_chapter_link = new_domain + \"/\" + each_link
    print each_chapter_link
    req = urllib2.Request(url=each_chapter_link)
    resp = urllib2.urlopen(req)
    html = resp.read()

    soup = BS(html, \'lxml\')
    content = soup.find(\"div\", {\"class\": \"bookyuanjiao\", \"id\": \"con\"})
    title = soup.title.text
    title = title.split(u\'_《三国演义》_诗词名句网\')[0]

    html = str(content)
    html = head + html + \"\"

    filename = path + \"\\\\\" + title + \".html\"
    print filename
    # write file
    output = open(filename, \'w\')
    output.write(html)
    output.close()

0.html的内容如下