// Delete all videos from playlist
        public static async Task <bool> Delete(ApplicationDbContext context, long PlayListID)
        {
            var entity = new JGN_Playlist_Videos {
                id = PlayListID
            };

            context.JGN_Playlist_Videos.Attach(entity);
            context.JGN_Playlist_Videos.Remove(entity);
            await context.SaveChangesAsync();

            PlayListBLL.Update_Video_Stat(context, PlayListID, 0); // update video statistic of play list
            return(true);
        }
        public static async Task <bool> Add(ApplicationDbContext context, long playlid_id, long contentid)
        {
            var _entity = new JGN_Playlist_Videos()
            {
                id         = playlid_id,
                contentid  = contentid,
                created_at = DateTime.Now
            };

            context.Entry(_entity).State = EntityState.Added;

            await context.SaveChangesAsync();

            // update video statistics
            int count = await PlayList_VideosBLL.Count(context, playlid_id); // count total no of videos in current playlist

            PlayListBLL.Update_Video_Stat(context, playlid_id, count);       // update video statistic of play list
            return(true);
        }