此代码是根据网络上其他人的代码优化而成的，
环境准备：
pip install lxml
pip install bs4
pip install urllib
1 #!/usr/bin/env python
2 #-*- coding: utf-8 -*-
3
4 import requests
5 from bs4 import BeautifulSoup
6 import os
7 import urllib
8 import random
9
10
11 class mzitu():
12
13 def all_url(self, url):
14 html = self.request(url)
15 all_a = BeautifulSoup(html.text, 'lxml').find('div', class_='all').find_all('a')
16 for a in all_a:
17 title = a.get_text()
18 print(u'开始保存：', title)
19 title = title.replace(':', '')
20 path = str(title).replace("?", '_')
21 if not self.mkdir(path): ##跳过已存在的文件夹
22 print(u'已经跳过：', title)
23 continue
24 href = a['href']
25 self.html(href)
26
27 def html(self, href):
28 html = self.request(href)
29 max_span = BeautifulSoup(html.text, 'lxml').find('div', class_='pagenavi').find_all('span')[-2].get_text()
30 for page in range(1, int(max_span) + 1):
31 page_url = href + '/' + str(page)
32 self.img(page_url)
33
34 def img(self, page_url):
35 img_html = self.request(page_url)
36 img_url = BeautifulSoup(img_html.text, 'lxml').find('div', class_='main-image').find('img')['src']
37 self.save(img_url, page_url)
38
39 def save(self, img_url, page_url):
40 name = img_url[-9:-4]
41 try:
42 img = self.requestpic(img_url, page_url)
43 f = open(name + '.jpg', 'ab')
44 f.write(img.content)
45 f.close()
46 except FileNotFoundError: ##捕获异常，继续往下走
47 print(u'图片不存在已跳过：', img_url)
48 return False
49
50 def mkdir(self, path): ##这个函数创建文件夹
51 path = path.strip()
52 isExists = os.path.exists(os.path.join("D:mzitu", path))
53 if not isExists:
54 print(u'建了一个名字叫做', path, u'的文件夹！')
55 path = path.replace(':','')
56 os.makedirs(os.path.join("D:mzitu", path))
57 os.chdir(os.path.join("D:mzitu", path)) ##切换到目录
58 return True
59 else:
60 print(u'名字叫做', path, u'的文件夹已经存在了！')
61 return False
62
63 def requestpic(self, url, Referer): ##这个函数获取网页的response 然后返回
64 user_agent_list = [
65 "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1"
65-1 "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0",
66 "Mozilla/5.0 (X11; CrOS i686 2268.111.0) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
67 "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.6 (KHTML, like Gecko) Chrome/20.0.1092.0 Safari/536.6",
68 "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.6 (KHTML, like Gecko) Chrome/20.0.1090.0 Safari/536.6",
69 "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/19.77.34.5 Safari/537.1",
70 "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.9 Safari/536.5",
71 "Mozilla/5.0 (Windows NT 6.0) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.36 Safari/536.5",
72 "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
73 "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
74 "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_0) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3",
75 "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
76 "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3",
77 "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
78 "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
79 "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3",
80 "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.0 Safari/536.3",
81 "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.24 (KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24",
82 "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/535.24 (KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24"
83 ]
84 ua = random.choice(user_agent_list)
85 headers = {'User-Agent': ua, "Referer": Referer} ##较之前版本获取图片关键参数在这里
86 content = requests.get(url, headers=headers)
87 return content
88
89 def request(self, url): ##这个函数获取网页的response 然后返回
90 headers = {
91 'User-Agent': "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1"}
92 content = requests.get(url, headers=headers)
93 return content
94
95
96 Mzitu = mzitu() ##实例化
97 Mzitu.all_url('http://www.mzitu.com/all/') ##给函数all_url传入参数 你可以当作启动爬虫（就是入口）
98 print(u'恭喜您下载完成啦！')
执行步骤：
重复执行代码的话已保存的不会再次下载保存
执行结果：
遇到的错误如何解决：
1、错误提示：requests.exceptions.ChunkedEncodingError: ("Connection broken: ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None)", ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None))
错误原因分析：访问量瞬间过大，被网站反爬机制拦截了
解决方法:稍等一段时间再次执行即可
2、requests.exceptions.ChunkedEncodingError: ("Connection broken: ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None)", ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None))
错误原因分析：可能对方服务器做了反爬
解决方法：requests手动添加一下header
