下載一個頁面的全部 pdf 文件

要下載裘宗燕老師的 數據結構與算法（Python 語言） 講義,

1. 使用正則表達式

#!/usr/bin/env python

import re
import urllib.request as request

baseurl = 'http://www.math.pku.edu.cn/teachers/qiuzy/ds_python/courseware/'
with request.urlopen(baseurl) as response:
    html = response.read().decode('gb2312')

pdfurls = re.findall(r'[^\"]*.pdf', html, re.I)
for name in pdfurls:
    request.urlretrieve(baseurl+name, name)
    print('下載{}成功'.format(name))

2. 使用 Beautiful Soup

#!/usr/bin/env python

import urllib.request as request
import bs4

baseurl = 'http://www.math.pku.edu.cn/teachers/qiuzy/ds_python/courseware/'
with request.urlopen(baseurl) as response:
    html = response.read()

soup = bs4.BeautifulSoup(html, 'lxml')
for link in soup.find_all('a'):
    name  = link.get('href')
    if 'pdf' in name:
        request.urlretrieve(baseurl+name, name)
        print('download {} success'.format(name))