public ForumDTO CreateForum(ForumDTO newForum)
        {
            Forum entity = mapper.Map <Forum>(newForum);

            try {
                var forum = _forumRepository.CreateForum(entity);
                _forumRepository.SaveChanges();
                return(mapper.Map <ForumDTO>(forum));
            }
            catch (Exception ex)
            {
                throw new ErrorOccurException(ex.Message);
            }
        }