python爬虫：将数据保存到本地

一.python语句存储

1.with open()语句

1 with open(name,mode,encoding) as file：
2   file.write()

name：包含文件名称的字符串;
mode：决定了打开文件的模式,只读/写入/追加等;
encoding：表示我们要写入数据的编码，一般为 utf-8 或者 gbk ;
file：表示我们在代码中对文件的命名。

2.w：只写模式，如果没有文件则自动创建

1 f.write("{} {} {} {}
".format(title,price,scrible,pic))

3.例子

1）

1 with open('a.txt','wb') as f:
2     for tag in soup.find_all('div',class_='service-item-pic'):
3         a_url = tag.find('a').get('href')
4         f.write(a_url)
5         f.write('
')

2）

1 for tag in soup.find_all('div',class_='service-item-pic'):
2     with open('3.txt', 'a') as f:             
3         a_url = tag.find('a').get('href')
4         f.write(a_url)
5         f.write('
')

二.保存图片

1.方法

首先用Beautiful Soup结合正则表达式的方式来提取所有链接：

1 links = soup.find_all('img', "origin_image zh-lightbox-thumb",src=re.compile(r'.jpg$'))

提取出所有链接后，使用request.urlretrieve来将所有链接保存到本地

2.例子

 1 import time
 2 from urllib import request
 3 from bs4 import BeautifulSoup
 4 import re
 5 url = r'https://www.zhihu.com/question/355015346/answer/892031308'
 6 headers = {'User-Agent':'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36'}
 7 page = request.Request(url, headers=headers)
 8 page_info = request.urlopen(page).read().decode('utf-8')
 9 soup = BeautifulSoup(page_info, 'html.parser')
10 links = soup.find_all('img', "origin_image zh-lightbox-thumb",src=re.compile(r'.jpg$'))
11 local_path = r'C:UsersAdministratorDesktop'
12 for link in links:
13     print(link.attrs['src'])
14     request.urlretrieve(link.attrs['src'], local_path+r'\%s.jpg' % time.time())