تفاوت AddSingleton – AddTransient – AddScoped – جلسه ۵۱

    public class StaticCategoryRepository : ICategoryRepository
    {
        List<Category> _categories = new()
        {
            new Category { ID = 1, CategoryName="Bill", Description="Category for recording cost of bills", Active=CategoryActiveOptions.Yes},
            new Category { ID = 2, CategoryName = "Rent", Description = "Category for recording montly rental cost", Active = CategoryActiveOptions.Yes },
            new Category { ID = 3, CategoryName = "Petrol", Description = "Category for recording cost of petrol (Gas)", Active = CategoryActiveOptions.Yes }
        };
        public IEnumerable<Category> GetAllCategories()
        {
            return _categories;
        }
    }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContextPool<WebAppDBContext>
                (options=> options.UseSqlServer(Configuration.GetConnectionString("CostDBConnectionSQLServer")));
            services.AddControllersWithViews();
            services.AddSingleton<ICostRepository, StaticCostRepository>();
            services.AddSingleton<ICategoryRepository, StaticCategoryRepository>();
        }

        private void LoadDropDownList()
        {
            var Categories = categoryRepository.GetAllCategories();
            List<SelectListItem> CategoryList = new();
            CategoryList.Add(new SelectListItem("Select a Category", "-1"));
            foreach (var category in Categories)
            {
                CategoryList.Add(new SelectListItem(category.CategoryName, category.ID.ToString()));
            }
            List<SelectListItem> PaymentMethodsList = new();
            PaymentMethodsList.Add(new SelectListItem("Select a Payment Method", ""));
            var PaymentMethods = Enum.GetValues(typeof(PaymentMethods)).Cast<PaymentMethods>().ToList();
            for (var i = 0; i < PaymentMethods.Count; i++)
            {
                PaymentMethodsList.Add(new SelectListItem(PaymentMethods[i].ToString(), i.ToString()));
            }
            ViewBag.Categories = CategoryList;
            ViewBag.PaymentMethods = PaymentMethodsList;
        }

        [HttpGet]
        public IActionResult Create()
        {
            LoadDropDownList();
            return View();
        }
        [HttpPost]
        public IActionResult Create(CreateCostViewModel model)
        {
             if (ModelState.IsValid)
            {
                Cost NewCost = new()
                {
                    Amount = model.Amount,
                    CategoryID = model.CategoryID,
                    Comment = model.Comment,
                    RegisteredDate = model.RegisteredDate,
                    PaymentMethod = model.PaymentMethod
                };
                costRepository.Create(NewCost);
                return RedirectToAction("Index");
            }
            LoadDropDownList();
            return View(model);
        }
        [HttpGet]
        public IActionResult Edit(int id)
        {
            var cost = costRepository.GetCostByID(id);
            LoadDropDownList();
            return View(cost);
        }
        [HttpPost]
        public IActionResult Edit(Cost editedCost)
        {
            if (ModelState.IsValid)
            {
                costRepository.Update(editedCost);
                return RedirectToAction("Index");
            }
            LoadDropDownList();
            return View(editedCost);
        }

    <div>
        <label asp-for="CategoryID" class="form-label"></label>
        <select asp-for=CategoryID asp-items="@ViewBag.Categories" class="form-select"></select>
        <span asp-validation-for="CategoryID" class="text-danger"></span>
    </div>
    <div>
        <label asp-for="PaymentMethod" class="form-label"></label>
        <select asp-for="PaymentMethod" class="form-select" asp-items="@ViewBag.PaymentMethods"></select>
        <span asp-validation-for="PaymentMethod" class="text-danger"></span>
    </div>

    public class CreateCostViewModel
    {
        [Column(TypeName = "decimal(18, 2)")]
        [Required]
        [DataType(DataType.Currency)]
        public decimal Amount { get; set; }
        [Required]
        [DataType(DataType.Date)]
        [Display(Name ="Registered Data")]
        public DateTime RegisteredDate { get; set; }
        [MaxLength(150)]
        public string Comment { get; set; }
        [RegularExpression("^\\d+$",ErrorMessage ="Please select a category")]
        [Display(Name ="Category")]
        public int CategoryID { get; set; }
        [Display(Name ="Payment Method")]
        [Required(ErrorMessage = "Please select a Payment Method")]
        public PaymentMethods? PaymentMethod { set; get; }
    }

    public class Cost
    {
        [Key]
        public int ID { get; set; }
        [Column(TypeName = "decimal(18, 2)")]
        [Required]
        public decimal Amount { get; set; }
        [Required]
        [DataType(DataType.Date)]
        public DateTime RegisteredDate { get; set; }
        [MaxLength(150)]
        public string Comment { get; set; }
        [Required]
        [RegularExpression("^\\d+$", ErrorMessage = "Please select a category")]
        public int CategoryID { get; set; }
        [ForeignKey(nameof(CategoryID))]
        public virtual Category Category { get; set; }
        [Required(ErrorMessage = "Please select a Payment Method")]
        public PaymentMethods? PaymentMethod { set; get; }
        public string InvoiceImagePath { get; set; }
    }