if __name__=="__main__":
    url = raw_input(\'请输入小组字符串代码如:haixiuzu\')
    beginPage = int(raw_input(\'请输入起始页码\'))
    endPage= int(raw_input(\'请输入结束页码\'))
    #构建url
    url = \'https://www.douban.com/group/\'+url+\'/discussion?start=\'
    #获取所有url
    getPageLink(url,beginPage,endPage)

def getPageLink(url,begin,end):
    """
    获取小组主页全部帖子链接
    :param url:
    :return:
    """
    #构建所有URL
    urlList = []
    #构建所有需要获取的链接
    for page in range(begin,end+1):
        pn = (page - 1) * 25
        urlList.append(str(url)+str(pn))
    #构建head
    headers = {\'User-Agent\':\'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36\'}
    #存放所有帖子链接
    linkList = []
    for i in urlList:
        Request =  urllib2.Request(i,headers=headers)
        html = urllib2.urlopen(Request).read()
        content=etree.HTML(html)
        #用xpath获取链接
        tempList=content.xpath(\'//td[@class="title"]/a/@href\')
        for t in tempList:
            linkList.append(t)
    getImgLink(linkList)

def getImgLink(url):
    """
    获取帖子里所有图片的链接
    :param url:
    :return:
    """
    headers = {
        \'Connection\': \'keep-alive\',
        \'Upgrade-Insecure-Requests\': \'1\',
        \'Referer\': \'https://www.douban.com/group/haixiuzu/discussion?start=0\',
        \'User-Agent\': \'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36\'
    }
    imgUrl = []
    for t in url:
        request = urllib2.Request(t,headers=headers)
        html = urllib2.urlopen(request).read()
        content = etree.HTML(html)
        #用xpath获取所有图片链接
        tempList = content.xpath(\'//div[@class="topic-content"]/div[@class="topic-figure cc"]/img/@src\')
        for t in tempList:
            imgUrl.append(t)
    savaImg(imgUrl)

def savaImg(imgList):
    """
    保存图片到本地
    :param imgList:
    :return:
    """
    headers = {
        \'User-Agent\': \'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36\'}
    #判断目录是否存在
    isExists = os.path.exists(\'img\')
    #如果不存在创建
    if not isExists:
        os.makedirs(\'img\')
    for t in imgList:
        request =  urllib2.Request(t,headers=headers)
        img = urllib2.urlopen(request).read()
        fileName = t[-10:]
        #写图片到指定目录
        with open(\'img\\\'+fileName,"wb") as writ:
            writ.write(img)