爬虫当当网前500书籍

import requests
import re
import json

def request_dandan(url):
    try:
        response = requests.get(url)
        if response.status_code == 200:
            return response.text
    except requests.RequestException:
        return None


def parse_result(html):
    pattern = re.compile(\'<li>.*?list_num.*?(\d+).</div>.*?<img src="(.*?)".*?class="name".*?title="(.*?)">.*?class="star">.*?class="tuijian">(.*?)</span>.*?class="publisher_info">.*?target="_blank">(.*?)</a>.*?class="biaosheng">.*?<span>(.*?)</span></div>.*?<p><span\sclass="price_n">¥(.*?)</span>.*?</li>\',re.S)
    items = re.findall(pattern,html)
    for item in items:
        yield {
            \'range\': item[0],
            \'iamge\': item[1],
            \'title\': item[2],
            \'recommend\': item[3],
            \'author\': item[4],
            \'times\': item[5],
            \'price\': item[6]
        }


def write_item_to_file(item):
    print(\'开始写入数据 ====> \' + str(item))
    with open(\'book.txt\', \'a\', encoding=\'UTF-8\') as f:
        f.write(json.dumps(item, ensure_ascii=False) + \'\n\')
        f.close()


def main(page):
    url = \'http://bang.dangdang.com/books/fivestars/01.00.00.00.00.00-recent30-0-0-1-\' + str(page)
    html = request_dandan(url)
    items = parse_result(html) # 解析过滤我们想要的信息
    for item in items:
        write_item_to_file(item)


if __name__ == "__main__":
    for i in range(1,26):
        main(i)