public override ChapterVersion GetPreviousChapter(string chapterId, string articleId)
        {
            using (TransactionScope transaction = new TransactionScope(mConfiguration))
            {
                ChapterVersionDataStore chapVersion = new ChapterVersionDataStore(transaction);

                IList <ChapterVersion> chVersList = chapVersion.FindAllItemsByArticleId(articleId);

                int seq = 0;

                if (!string.IsNullOrEmpty(chapterId))  // if this is null then the first chapter is loaded by default.
                {
                    seq = chVersList.IndexOf(chVersList.First(x => x.Id.Equals(chapterId)));
                }

                if (seq == 0)
                {
                    return(new ChapterVersion());
                }
                else
                {
                    if (seq != 0)
                    {
                        return(chVersList.ElementAt(seq - 1));
                    }
                    else
                    {
                        return(new ChapterVersion());
                    }
                }
            }
        }
        public override IList <ChapterVersion> GetAllItemsByArticleId(string articleId)
        {
            using (TransactionScope transaction = new TransactionScope(mConfiguration))
            {
                ChapterVersionDataStore chapVersion = new ChapterVersionDataStore(transaction);

                IList <ChapterVersion> dsChapters = chapVersion.FindAllItemsByArticleId(articleId);

                return(dsChapters);
            }
        }