Courses.Buisness.CategoryService.GetByID C# (CSharp) 메소드

        public CategoryViewModel GetByID(int id)
        {
            var category = categoryRepository.Get(id);
            return (category == null) ? null : Convert(category);
        }

 public void GetByIDTest()
 {
     ICategoryService _categoryService = new CategoryService(new CategoryRepository(), new CategoryFilterFactory());
     CategoryViewModel _categoryViewModel = GetCategoryViewModel();
     _categoryService.Add(_categoryViewModel);
     Assert.IsNotNull(_categoryService.GetByID(1));
 }