python 实现文件下载

Requests库，高度封装的http库

import requests

url = 'http://down.sandai.net/thunder9/Thunder9.0.18.448.exe'
filename = url.split('/')[-1]  #获取文件名
r = requests.get(url,stream = True)

with open(filename,'wb') as f:
    p = 0  #下载计数器
    chunk_size = 4096 #块大小
    try:
        while True:
            for data in r.iter_content(chunk_size):
                p += f.write(data)

                print('%d' % (p))

    except Exception as e:
        print(e)
    finally:
        print('下载完毕！')
        

urllib库，操作上能比Requests灵活一点，没有特殊需求的话基本没什么差别

import urllib.request

url = 'http://down.sandai.net/thunder9/Thunder9.0.18.448.exe'
resp = urllib.request.urlopen(url)
filename = url.split('/')[-1]
with open(filename,'wb') as f:
    p = 0 #下载计数
    buffsize = 4096 #块大小
    try:
        while True:
            buff = resp.read(buffsize)
            if not buff:    #buff为空，即下载完毕，结束循环
                break
            p += f.write(buff)
            print('%d' % p)
    except Exception as e:
        print(e)
    finally:
        print('下载完毕！')

还有个一句话的 

import urllib

urllib.urlretrieve(url, ‘test.jpg’)