python3入门教程

python ： 3.5

jdk ： 1.7

eclipse ： 4.5.2（有点低了，需要对应Neon 4.6,不然总是会弹出提示框）

应该学习最新版本的 Python 3 还是旧版本的 Python 2.7？

MySqlDB官网只支持Python3.4，这里Python3.5使用第三方库PyMysql连接Mysql数据库。

http://dev.mysql.com/downloads/connector/python/2.0.html

PyMysql下载地址：

https://pypi.python.org/pypi/PyMySQL#downloads

Windows下安装方法：

下载解压后，进入PyMySql-0.6.7目录，执行python setup.py install安装

test1.py

 import urllib.request as request
 def baidu_tieba(url, begin_page, end_page):
     for i in range(begin_page, end_page + 1):
         sName = 'D:/360Downloads/test/'+str(i).zfill(5)+'.html'
         print('正在下载第'+str(i)+'个页面, 并保存为'+sName)
         m = request.urlopen(url+str(i)).read()
         with open(sName,'wb') as file:
             file.write(m)
         file.close()
 if __name__ == "__main__":
     url = "http://tieba.baidu.com/p/"
     begin_page = 1
     end_page = 3
     baidu_tieba(url, begin_page, end_page)

test2.py

 import urllib.request as request
 import re
 import os
 import urllib.error as error
 def baidu_tieba(url, begin_page, end_page):
     count = 1
     for i in range(begin_page, end_page + 1):
         sName = 'D:/360Downloads/test/' + str(i).zfill(5) + '.html'
         print('正在下载第' + str(i) + '个页面, 并保存为' + sName)
         m = request.urlopen(url + str(i)).read()
         # 创建目录保存每个网页上的图片
         dirpath = 'D:/360Downloads/test/'
         dirname = str(i)
         new_path = os.path.join(dirpath, dirname)
         if not os.path.isdir(new_path):
             os.makedirs(new_path)
         page_data = m.decode('gbk', 'ignore')
         page_image = re.compile('<img src=\"(.+?)\"')
         for image in page_image.findall(page_data):
             pattern = re.compile(r'^http://.*.png$')
             if  pattern.match(image):
                 try:
                     image_data = request.urlopen(image).read()
                     image_path = dirpath + dirname + '/' + str(count) + '.png'
                     count += 1
                     print(image_path)
                     with open(image_path, 'wb') as image_file:
                         image_file.write(image_data)
                     image_file.close()
                 except error.URLError as e:
                     print('Download failed')
         with open(sName, 'wb') as file:
             file.write(m)
         file.close()
 if __name__ == "__main__":
     url = "http://tieba.baidu.com/p/"
     begin_page = 1
     end_page = 3
     baidu_tieba(url, begin_page, end_page)

test3.py

 #python3.4 爬虫教程
 #爬取网站上的图片
 #林炳文Evankaka(博客：http://blog.csdn.net/evankaka/)
 import urllib.request
 import socket
 import re
 import sys
 import os
 targetDir = r"D:\PythonWorkPlace\load"  #文件保存路径
 def destFile(path):
     if not os.path.isdir(targetDir):
         os.makedirs(targetDir)
     pos = path.rindex('/')
     t = os.path.join(targetDir, path[pos+1:])
     print(t)
     return t
 if __name__ == "__main__":  #程序运行入口
     weburl = "http://www.douban.com/"
     webheaders = {'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:23.0) Gecko/20100101 Firefox/23.0'}
     req = urllib.request.Request(url=weburl, headers=webheaders)  #构造请求报头
     webpage = urllib.request.urlopen(req)  #发送请求报头
     contentBytes = webpage.read()
     for link, t in set(re.findall(r'(https:[^\s]*?(jpg|png|gif))', str(contentBytes))):  #正则表达式查找所有的图片
         print(link)
         try:
             urllib.request.urlretrieve(link, destFile(link)) #下载图片
         except:
             print('失败') #异常抛出

test4.py

 '''
 第一个示例：简单的网页爬虫

 爬取豆瓣首页
 '''

 import urllib.request

 #网址
 url = "http://bj.58.com/caishui/28707491160259x.shtml?adtype=1&entinfo=28707491160259_0&adact=3&psid=156713756196890928513274724"

 #请求
 request = urllib.request.Request(url)

 #爬取结果
 response = urllib.request.urlopen(request)

 data = response.read()

 #设置解码方式
 data = data.decode('utf-8')

 #打印结果
 print(data)

 #打印爬取网页的各类信息

 # print(type(response))
 # print(response.geturl())
 # print(response.info())
 # print(response.getcode())

test5.py

 #!/usr/bin/env python
 #-*-coding: utf-8 -*-
 import re
 import urllib.request as request
 from bs4 import BeautifulSoup as bs
 import csv
 import os
 import sys
 from imp import reload
 reload(sys)

 def GetAllLink():
     num = int(input("爬取多少页:>"))
     if not os.path.exists('./data/'):
         os.mkdir('./data/')

     for i in range(num):
         if i+1 == 1:
             url = 'http://nj.58.com/piao/'
             GetPage(url, i)
         else:
             url = 'http://nj.58.com/piao/pn%s/' %(i+1)
             GetPage(url, i)

 def GetPage(url, num):
     Url = url
     user_agent = 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:32.0) Gecko/20100101 Firefox/32.0'
     headers = { 'User-Agent' : user_agent }
     req = request.Request(Url, headers = headers)
     page = request.urlopen(req).read().decode('utf-8')
     soup = bs(page, "html.parser")
     table = soup.table
     tag = table.find_all('tr')
     # 提取出所需的那段
     soup2 = bs(str(tag), "html.parser")
     title = soup2.find_all('a','t')         #标题与url
     price = soup2.find_all('b', 'pri')      #价格
     fixedprice = soup2.find_all('del')      #原价
     date = soup2.find_all('span','pr25')    #时间 

     atitle = []
     ahref = []
     aprice = []
     afixedprice = []
     adate = []

     for i in title:
         #print i.get_text(), i.get('href')
         atitle.append(i.get_text())
         ahref.append(i.get('href'))
     for i in price:
         #print i.get_text()
         aprice.append(i.get_text())
     for i in fixedprice:
         #print j.get_text()
         afixedprice.append(i.get_text())
     for i in date:
         #print i.get_text()
         adate.append(i.get_text())

     csvfile = open('./data/ticket_%s.csv'%num, 'w')
     writer = csv.writer(csvfile)
     writer.writerow(['标题','url','售价','原价','演出时间'])
     '''
     每个字段必有title，但是不一定有时间date
     如果没有date日期，我们就设为'---'
     '''
     if len(atitle) > len(adate):
         for i in range(len(atitle) - len(adate)):
             adate.append('---')
         for i in range(len(atitle) - len(afixedprice)):
             afixedprice.append('---')
         for i in range(len(atitle) - len(aprice)):
             aprice.append('---')

     for i in range(len(atitle)):
             message = atitle[i]+'|'+ahref[i]+'|'+aprice[i]+ '|'+afixedprice[i]+'|'+ adate[i]
             writer.writerow([i for i in str(message).split('|')])
     print ("[Result]:> 页面 %s 信息保存完毕!"%(num+1))
     csvfile.close()

 if __name__ == '__main__':
     GetAllLink()

test6.py

 #!/usr/bin/env python
 #-*-coding: utf-8 -*-
 import urllib.request as request
 from bs4 import BeautifulSoup as bs
 import sys
 from imp import reload
 reload(sys)

 def GetAllLink():
     num = int(input("爬取多少页:>"))

     for i in range(num):
         if i+1 == 1:
             url = 'http://bj.58.com/caishui/?key=%E4%BB%A3%E7%90%86%E8%AE%B0%E8%B4%A6%E5%85%AC%E5%8F%B8&cmcskey=%E4%BB%A3%E7%90%86%E8%AE%B0%E8%B4%A6%E5%85%AC%E5%8F%B8&final=1&jump=1&specialtype=gls'
             GetPage(url, i)
         else:
             url = 'http://bj.58.com/caishui/pn%s/'%(i+1)+'?key=%E4%BB%A3%E7%90%86%E8%AE%B0%E8%B4%A6%E5%85%AC%E5%8F%B8&cmcskey=%E4%BB%A3%E7%90%86%E8%AE%B0%E8%B4%A6%E5%85%AC%E5%8F%B8&final=1&specialtype=gls&PGTID=0d30215f-0000-1941-5161-367b7a641048&ClickID=4'
             GetPage(url, i)

 def GetPage(url, num):
     Url = url
     user_agent = 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:32.0) Gecko/20100101 Firefox/32.0'
     headers = { 'User-Agent' : user_agent }
     req = request.Request(Url, headers = headers)
     page = request.urlopen(req).read().decode('utf-8')
     soup = bs(page, "html.parser")
     table = soup.table
     tag = table.find_all('tr')

     # 提取出所需的那段
     soup2 = bs(str(tag), "html.parser")

     title = soup2.find_all('a','t')         #标题与url
     companyName = soup2.find_all('a','sellername') #公司名称

     atitle = []
     ahref = []
     acompanyName = []

     for i in title:
         atitle.append(i.get_text())
         ahref.append(i.get('href'))
     for i in companyName:
         acompanyName.append(i.get_text())
     for i in range(len(ahref)):
         getSonPage(str(ahref[i]))

 def getSonPage(url):
     Url = url
     user_agent = 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:32.0) Gecko/20100101 Firefox/32.0'
     headers = { 'User-Agent' : user_agent }
     req = request.Request(Url, headers = headers)
     page = request.urlopen(req).read().decode('utf-8')
     soup = bs(page, "html.parser")
     print("=========================")
     #类别
     print(soup.find('div','su_con').get_text())
     #服务区域
     print(soup.find('div','su_con quyuline').get_text())
     #联 系 人
     print(soup.find_all('ul','suUl')[0].find_all('li')[2].find_all('a')[0].get_text())
     #商家地址
     print(soup.find_all('ul','suUl')[0].find_all('li')[3].find('div','su_con').get_text().replace("\n",'').replace("\r",'').replace('\t','').replace(' ',''))
     #服务项目
     print(soup.find('article','description_con').get_text().replace("_____________________________________","\n\r").replace("___________________________________","\n\r").replace("（以下为公司北京区域分布图）",""))
     print("=========================")

 if __name__ == '__main__':
     GetAllLink()

test7.py

 import pymysql
 conn = pymysql.connect(host='192.168.1.102', port=3306,user='root',passwd='',db='test',charset='UTF8')
 cur = conn.cursor()
 cur.execute("select version()")
 for i in cur:
     print(i)
 cur.close()
 conn.close()