爬虫项目 之(一) --- urllib 和 正则re

from urllib import request,parse
from time import sleep
import re

# 1、【数据的获取】
# 封装一个函数，用于将url转化成一个请求对象
def request_by(url,page):
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.80 Safari/537.36'}
    if page==1:
        page_url = url + ".html"
    else:
        page_url = url +"_"+ str(page) + ".html"
    print("正在访问：",page_url)
    req = request.Request(url=page_url,headers=headers)
    return  req
# 封装一个函数，用于对请求对象发起请求并且把响应体返回出去
def get_html_from(req):
    res = request.urlopen(req)
    # 每请求一次要休眠一段时间
    sleep(1)
    return res.read().decode("utf-8")

# 2、【数据的解析】
def anylasis_data(html):
    pat = re.compile(r'<div class="box picblock.*?<img src2="(.*?)"',re.S)
    imgs = pat.findall(html)
    return imgs

# 3、数据的存储
def download_imgs(imgs):
    for img in imgs:
        # http://pic1.sc.chinaz.com/Files/pic/pic9/201904/zzpic17564_s.jpg
        # 生成图片的名字
        img_name = img.split("/")[-1]
        print("正在下载图片：",img)
        request.urlretrieve(url=img,filename="./meinv/"+img_name)
        sleep(1)

if __name__ == '__main__':
    page_url = "http://sc.chinaz.com/tupian/meinvxiezhen"

    for i in range(1,2):
        req = request_by(url=page_url,page=i)
        res = get_html_from(req)
        imgs = anylasis_data(res)
        download_imgs(imgs)