1. 链接格式：http://video.superlib.com/shipin0(server_id)/cx/(id)/0/(teacher_id)/(video_number).flv
2. 链接格式分析：
   • server_id : 范围1-4
   • id : 每个课程都对应一个，但一个video_id可能对应多个课程
   • teacher_id : 每位教师的编号
   • video_number : 每个视频对应编号
3. 来源与组成：
   • server_id : 每个视频对应的服务器都不相同，仅能一个个的测试文件所在的服务器
   • id : 理想状态下根据课程页面如：http://video.chaoxing.com/serie_400008049.shtml，其中8049即id；但：http://video.chaoxing.com/serie_400015556.shtml的id却不为15556，而和前者相同，为8049；所以无法仅仅根据课程页面分析得知id；一个方法是使用idm下载一个视频分析id后指定，也请知道方法其它的朋友不吝赐教。
   • teacher_id : 可以根据教师介绍页面链接获取，如：http://video.chaoxing.com/teacher_11996.shtml，其中11996即为teacher_id
   • video_number : 与每个视频页面的链接中获取：如：http://video.chaoxing.com/play_400015556_101447.shtml，其中101447即video_number
4. Python代码：

   # *-* coding:utf-8 *-*import requestsfrom bs4 import BeautifulSoupimport osimport sysimport getoptclass Dlcx(object):#初始化：检测链接是否有效    def __init__(self, url, items = ‘all‘, output = ‘.\\‘, raw_options=‘‘, video_id=""):        if url[:33] == ‘http://video.chaoxing.com/serie_4‘ and url[41:] == ‘.shtml‘:            self.url = url            self.serverlist = [‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘]            self.items = items            self.output = output+"\\"            self.raw_options = raw_options            self.video_id = video_id        else:            print(‘请检查链接格式, \"cxdl.exe -h\" 获取帮助‘)            exit        def getpage(self):        session = requests.Session()        headers = {‘User-Agent‘:‘Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:47.0) Gecko/20100101 Firefox/47.0‘}        self.r = session.get(self.url)    def usefulserver(self):        for j in self.serverlist:            test_url = self.filelist[1][1][:33] + j + self.filelist[1][1][34:]#           print(test_url)            try:                test_r = requests.get(test_url, stream=True)            except :#                print(j+"号服务器连接失败！")                if j == ‘5‘:                    exit            else:                self.server = j                print("文件位于 " + j + " 号服务器")                break        for i in range(0, len(self.filelist)):            self.filelist[i][1] = self.filelist[i][1][:33] + self.server + self.filelist[i][1][34:]            self.filelist[i][0] = self.output + self.filelist[i][0]                    def getdllist(self):        for i in range(34,41):            if self.url[i] != ‘0‘:                not_zero = i                break        video_id = self.url[not_zero:self.url.index(‘shtml‘)-1]        if self.video_id != ‘‘:            video_id = self.video_id        rtext = self.r.text        teacher_index = rtext.index(‘/teacher_‘)        teacher_id = rtext[teacher_index+9: teacher_index+16]        teacher = teacher_id[:teacher_id.index(‘.‘)]        screen = BeautifulSoup(rtext, ‘lxml‘).select(‘.screen‘)[1]        all_a = screen.find_all(‘a‘)        self.filelist = []        for i in range(0,len(all_a)):            proc = all_a[i]            href = proc.attrs[‘href‘]            filename = ‘第‘+str(i+1)+‘集-‘+proc.attrs[‘title‘]+‘.flv‘            href_id = href[href.rfind(‘_‘)+1: href.index(‘.‘)]            filehref = ‘http://video.superlib.com/shipin0‘+ ‘0‘ +‘/cx/‘+video_id+‘/0/‘+teacher+‘/‘+href_id+‘.flv‘            self.filelist.append([filename, filehref])            def dl(self):        if items == ‘all‘:            for task in self.filelist:                os.system(‘wget.exe -O ‘+ task[0] + ‘ ‘ + task[1])        else:            if max(self.items) > len(self.filelist) or min(self.items) < 1:                 print("请求下载的编号不在编号区间")                 sys.exit(1)            for i in self.items:                rtc = os.system(‘wget.exe -c -O ‘+self.filelist[i-1][0]+‘ ‘+self.raw_options+‘ ‘+self.filelist[i-1][1])                while rtc:                    os.system(‘wget.exe -c -O ‘+self.filelist[i-1][0]+‘ ‘+self.raw_options+‘ ‘+self.filelist[i-1][1])def extend(string, toint=False):    ext = []    start =0    end = 0    i = 0    while i < len(string):        while string[i] != ‘,‘:            i += 1            if i == (len(string)):                break        end = i        i += 1        if toint:            s = string[start:end]            if ‘-‘ in s:                if s.index(‘-‘) == 0:                    sys.exit(‘不允许存在负数编号‘)                for j in range(int(s[:s.index(‘-‘)]),int(s[s.index(‘-‘)+1:])+1):                    ext.append(j)            else:                ext.append(int(string[start:end]))        else:            ext.append(string[start:end])        start = end+1    return ext#mainif __name__ == "__main__" :    version = "cxdl version 0.3  Time:2017/7/15  Author:iokeyz@Github  Blog:yaoz.cnblogs.com"    helpdoc = ‘‘‘++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++用法：    -h , --help                      获取帮助信息    -v , --version                   获取版本信息    -s , --serie                     超星课程列表地址,多个用逗号分隔,如："http://video.chaoxing.com/serie_400000001.shtml"    -g , --get                       选择课程列表的某项或某几项(逗号分隔)下载,如："1,5-10,11"    -o , --output                    选择输出路径,如："D:\Download\\"    -r , --raw                       支持wget源命令，如："--limit-rate=1024k"    -i , --id                        指定video_id，某些情况下，无法仅由列表获取下载链接                                     获取方法:使用idm下载其中任意一个视频，对照如下链接格式，使用-i参数指定video_id即可                                     http://video.superlib.com/shipin0(server_id)/cx/(video_id)/0/(teacher_id)/(video_number).flv例如：    >>> cxdl.exe -s http://video.chaoxing.com/serie_400015556.shtml -r "--limit-rate=20k" -g 1,45-58,25 -i 8049++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++  ‘‘‘    try:        opts, args = getopt.getopt(sys.argv[1:], "hvs:g:o:r:i:", ["help","version","serie=","get=","output=","raw=","id="])        all_opt = []        all_val = []        for opt_val in opts:            all_opt.append(opt_val[0])            all_val.append(opt_val[1])        items = None        output = None        video_id= ‘‘        raw_options = ‘‘        if ‘-v‘ in all_opt or ‘--version‘ in all_opt:            print(version)        if ‘-h‘ in all_opt or ‘--help‘ in all_opt:            print(helpdoc)        elif ‘-s‘ in all_opt or ‘--serie‘ in all_opt:            if ‘-s‘ in all_opt:                series = extend(all_val[all_opt.index(‘-s‘)], toint=False)            else:                series = extend(all_val[all_opt.index(‘--serie‘)], toint=False)            if ‘-g‘ in all_opt:                items = extend(all_val[all_opt.index(‘-g‘)], toint=True)            elif ‘--get‘ in all_opt:                items = extend(all_val[all_opt.index(‘--get‘)], toint=True)            if ‘-o‘ in all_opt:                output = all_val[all_opt.index(‘-o‘)]            elif ‘--output‘ in all_opt:                output = all_val[all_opt.index(‘--output‘)]            if ‘-r‘ in all_opt:                raw_options = all_val[all_opt.index(‘-r‘)]            elif ‘--raw‘ in all_opt:                raw_options = all_val[all_opt.index(‘--raw‘)]            if ‘-i‘ in all_opt:                video_id = all_val[all_opt.index(‘-i‘)]            elif ‘--id‘ in all_opt:                video_id = all_val[all_opt.index(‘--id‘)]            for i in range(0, len(series)):                if items == None:                    items = ‘all‘                if output == None:                    output = ‘.\\‘                if raw_options == None:                    raw_options = ‘‘                dlcx = Dlcx(series[i], items, output, raw_options, video_id)                dlcx.getpage()                dlcx.getdllist()                print("开始下载："+series[i])                print("下载内容："+str(items))                print("保存地址："+output)                print("下载参数："+raw_options+" -O filename.flv")                dlcx.usefulserver()                dlcx.dl()        else:            print(helpdoc)    except getopt.GetoptError:         print("getopt error!")        sys.exit(1)

5. 注意：需要配合wget.exe使用，也可以自己修改使用其他下载工具如aria2c.exe
6. 封装：cxdl.exe

超星学术视频下载分析