import requestsimport reimport jsonimport timefrom bs4 import BeautifulSoupfrom pyquery import PyQuery as pqfrom lxml import etree# 获取页面源码def get_one_page(url):    try:        headers = {  # 伪装请求头            'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.75 Safari/537.36'        }        response = requests.get(url, headers=headers)  # 构造响应        if response.status_code == 200:  # 判断状态码            return response.text        return None    except requests.exceptions.RequestException as r:        return None# 正则表达式提取源码关键信息def parse_one_page(html):    # 正则表达式查询目标信息    pattern = re.compile(        '
    
     .*?board-index.*?>(\d+).*?data-src="(.*?)".*?name">
     
      (.*?).*?star">(.*?)
      
.*?releasetime">(.*?)
      
.*?integer">(.*?).*?fraction">(.*?).*?
     
    
', re.S)    items = re.findall(pattern, html)    for item in items:        # 包含yield表达式的函数是特殊的函数，叫做生成器函数(generator function)，被调用时将返回一个迭代器（iterator），调用时可以使用next或send(msg)。它的用法与return相似，区别在于它会记住上次迭代的状态，继续执行。        yield{  # yield关键字            'index': item[0],            'image': item[1],            'title': item[2].strip(),            'actor': item[3].strip()[3:],  # if len(item[3])>3 else '',            'time': item[4].strip()[5:],  # if len(item[4])>5 else '',            'score': item[5].strip()+item[6].strip()        }#Xpath提取信息def xpath_demo(html):    html=etree.HTML(html)    str1='//dd['    for i in range(10):        yield{  # yield关键字            'index': html.xpath(str1+str(i)+']/i/text()'),            'image': html.xpath(str1+str(i)+']/a/img[@class="board-img"]/@data-src'),            'title': html.xpath(str1+str(i)+']//p/a[@data-act="boarditem-click"]/text()'),            'actor': ''.join(html.xpath(str1+str(i)+']//p[@class="star"]/text()')).strip(),            'time': html.xpath(str1+str(i)+']//p[@class="releasetime"]/text()'),            'score': ''.join(html.xpath(str1+str(i)+']//p[@class="score"]/i/text()')),        }# bs4提取关键信息def bs4_demo(html):    soup = BeautifulSoup(html, 'lxml')    # pq=PyQuery(html)    # for item in pq('dd img/.board-img')    for dd in soup.find_all(name='dd'):        yield{            'index': dd.find(name='i', attrs={'class': 'board-index'}).string.strip(),#去掉前后空格            'image': dd.find(name='img', attrs={'class': 'board-img'})['data-src'],            'title': dd.find(name='p', attrs={'class': 'name'}).string.strip(),            'actor': dd.find(name='p', attrs={'class': 'star'}).string.strip(),            'time': dd.find(name='p', attrs={'class': 'releasetime'}).string.strip(),            'score': dd.find(name='i', attrs={'class': 'integer'}).string+dd.find(name='i', attrs={'class': 'fraction'}).string        }#pyquery css筛选信息def pyquery_demo(html):    doc=pq(html)    for dd in doc('dd').items():        yield{            'index': dd.find('i.board-index').text(),#获取文本            'image': dd.find('img.board-img').attr('data-src'),#获取属性            'title': dd.find('p.name a').text(),            'actor': dd.find('p.star').text(),            'time': dd.find('p.releasetime').text(),            'score': dd.find('p.score i.integer').text()+dd.find('p.score i.fraction').text()        }def write_to_file(content):    with open('/Users/zz/Desktop/result.txt', 'a', encoding='utf-8') as f:        # json.dumps()实现字典的序列化，ensure_ascii=False保证输出非Unicode编码        f.write(json.dumps(content, ensure_ascii=False)+'/n')def main(offset):    url = 'https://maoyan.com/board/4?offset='+str(offset)    html = get_one_page(url)    # for item in parse_one_page(html):    #for item in bs4_demo(html):    #for item in pyquery_demo(html):    for item in xpath_demo(html):        print(item)        # write_to_file(item)  # 写入文件if __name__ == '__main__':  # 是否从控制台执行    for i in range(10):        main(offset=i*10)        time.sleep(1)#避免操作过快被识别