public async Task <ActionResult> Index()
        {
            var input = new GetCategorysInput()
            {
                MaxResultCount = 20, SkipCount = 0
            };
            var categorys = await _categoryAppService.GetPaged(input);

            return(View(categorys));
        }
        public async Task <PagedResultDto <CategoryListDto> > GetPaged(GetCategorysInput input)
        {
            var query = _entityRepository.GetAll();
            // TODO:根据传入的参数添加过滤条件


            var count = await query.CountAsync();

            var entityList = await query
                             .OrderBy(input.Sorting).AsNoTracking()
                             .PageBy(input)
                             .ToListAsync();

            // var entityListDtos = ObjectMapper.Map<List<CategoryListDto>>(entityList);
            var entityListDtos = entityList.MapTo <List <CategoryListDto> >();

            return(new PagedResultDto <CategoryListDto>(count, entityListDtos));
        }