python3 requests库实现多图片爬取教程

import re
import requests
import os
 
name=input('输入文件夹名称:')
robot='C:/Users/lenovo/Desktop/'+name+'/'
kv={'user-agent':'mozilla/5.0'}
 
#获取url对应的源码页面
def getHTMLText(url):
 try:
  r=requests.get(url,timeout=30,headers=kv)
  r.raise_for_status()
  r.encoding=r.apparent_encoding
  return r.text
 except:
  return ''
 
#解析url源码页面
def parserHTML(html):
#正则表达式为获取ObjURL
 pattern=r'"ObjURL":"(.*?)"'
 reg=re.compile(pattern)
 urls=re.findall(reg,html)
 return urls
 
#下载图片
def download(List):
 for url in List:
  try:
   path=robot+url.split('/')[-1]
   url=url.replace('\\','')
   r=requests.get(url,timeout=30)
   r.raise_for_status()
   r.encoding=r.apparent_encoding
   if not os.path.exists(robot):
    os.makedirs(robot)
   if not os.path.exists(path):
    with open(path,'wb') as f:
     f.write(r.content)
     f.close()
     print(path+' 文件保存成功')
   else:
    print('文件已经存在')
  except:
   continue
 
#通过Requests URL请求到更多的url源码页面
def getmoreurl(num,word):
 ur=[]
 url=r'http://image.baidu.com/search/acjson?tn=resultjson_com&ipn=rj&ct=201326592&is=&fp=result&queryWord={word}&cl=2&lm=-1&ie=utf-8&oe=utf-8&adpicid=&st=-1&z=&ic=0&word={word}&s=&se=&tab=&width=&height=&face=0&istype=2&qc=&nc=1&fr=&cg=girl&pn={pn}&rn=30'
 for x in range(1,num+1):
#word为搜索关键词，num为想获取的页面数量
  u=url.format(word=word,pn=30*x)
  ur.append(u)
 return ur
 
def main():
 n=int(input('输入想下载多少张图片(n*30)：'))
 word=input('输入想下载的图片:')
#初始页面url
 url='http://image.baidu.com/search/index?tn=baiduimage&ipn=r&ct=201326592&cl=2&lm=-1&st=-1&fm=result&fr=&sf=1&fmq=1499773676062_R&pv=&ic=0&nc=1&z=&se=1&showtab=0&fb=0&width=&height=&face=0&istype=2&ie=utf-8&word={word}'.format(word=word)
 html=getHTMLText(url)
 urls=parserHTML(html)
 download(urls)
#下面操作获取的更多页面图片
 url1=getmoreurl(n,word)
 for i in range(n):
  html1=getHTMLText(url1[i])
  urls1=parserHTML(html1)
  download(urls1)
 
main()