- Добавил репозиторий и сервис для бренда.

- вынес логику в репозитории и сервисы из PhoneController.
- обернул try catch PoneController.
- дополнил мапперы, добавил проверку на null;

PhoneStore/Controllers/PhonesController.cs

 using System;
-using System.Collections.Generic;
 using System.IO;
-using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc;
-using Microsoft.EntityFrameworkCore;
-using PhoneStore.Helpers;
+using PhoneStore.Exceptions;
 using PhoneStore.Mappers;
 using PhoneStore.Models;
 using PhoneStore.Services.Interfaces;
-using PhoneStore.ViewModels;
-using PhoneStore.ViewModels.Account;
 using PhoneStore.ViewModels.PhoneViewModels;
 
 namespace PhoneStore.Controllers
 {
     public class PhonesController : Controller
     {
-        private readonly MobileContext _db;
         private readonly IPhoneService _phoneService;
+        private readonly IBrandService _brandService;
 
         public PhonesController(
             MobileContext db,
-            IPhoneService phoneService)
+            IPhoneService phoneService, IBrandService brandService)
         {
-            _db = db;
             _phoneService = phoneService;
+            _brandService = brandService;
         }
        
         [HttpGet]
         public IActionResult Index(int? brandId)
         {
-            IEnumerable<Brand> brands = _db.Brands;
-            IQueryable<Phone> phones = _db.Phones.AsQueryable();
-
-            if (brandId is > 0)
-                phones = _db.Phones.Where(p => p.BrandId == brandId);
-
-            return View(new IndexViewModel
+            try
+            {
+                return View(_phoneService.GetIndexViewModel(brandId));
+            }
+            catch (EntityNotFoundException e)
             {
-                Brands = brands,
-                Phones = phones.ToList()
-            });
+                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+            }
+            catch (Exception e)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
         }
 
         [HttpGet]
         public IActionResult Create()
         {
-            IPhoneEditable model = new PhoneCreateViewModel
+            try
+            {
+                return View(_phoneService.GetCreateViewModel());
+            }
+            catch (EntityNotFoundException e)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+            }
+            catch (Exception e)
             {
-                Brands = _db.Brands.ToList()
-            };
-            return View(model);
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
         }
         
         [HttpPost]
@@ -66,77 +69,122 @@ namespace PhoneStore.Controllers
                     return RedirectToAction("Index");
                 }
 
-                model.Brands = _db.Brands.ToList();
+                model.Brands = _brandService.GetAll();
                 return View("Create", model);
             }
-            //TODO: Добавить кастомный exception
+            catch (EntityNotFoundException e)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+            }
             catch (FileNotFoundException)
             {
                 return RedirectToAction("Error", "Errors", new {statusCode = 666});
             }
             catch(Exception)
             {
-                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
             }
         }
 
         [HttpGet]
         public IActionResult Delete(int phoneId)
         {
-            var phone = _db.Phones.FirstOrDefault(p => p.Id == phoneId);
+            try
+            {
+                var phone = _phoneService.GetById(phoneId);
                 if (phone is null)
                     return RedirectToAction("Error", "Errors", new {statusCode = 777});
             
                 return View(phone);
             }
+            catch (EntityNotFoundException e)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+            }
+            catch (FileNotFoundException)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 666});
+            }
+            catch(Exception)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
+        }
         
         [HttpPost]
         [ActionName("Delete")]
         public IActionResult Confirm(int phoneId)
+        {
+            try
             {
                 //TODO: Добавить удаление файла изображения.
-            var phone = _db.Phones.FirstOrDefault(p => p.Id == phoneId);
+                var phone = _phoneService.GetById(phoneId);
                 if (phone is null)
                     return RedirectToAction("Error", "Errors", new {statusCode = 777});
-            _db.Phones.Remove(phone);
-            _db.SaveChanges();
+                _phoneService.Delete(phoneId);
                 return RedirectToAction("Index");
             }
+            catch (EntityNotFoundException e)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+            }
+            catch (FileNotFoundException)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 666});
+            }
+            catch(Exception)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
+        }
 
         [HttpGet]
         public IActionResult Edit(int phoneId)
         {
-            var brands = _db.Brands.ToList();
-            var phone = _db.Phones.FirstOrDefault(p => p.Id == phoneId);
-            if (phone is null)
+            try
+            {
+                return View(_phoneService.GetEditViewModel(phoneId));
+            }
+            catch (EntityNotFoundException e)
+            {
                 return RedirectToAction("Error", "Errors", new {statusCode = 777});
-            
-            IPhoneEditable model = new PhoneEditViewModel
+            }
+            catch (FileNotFoundException)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 666});
+            }
+            catch(Exception)
             {
-                Id = phone.Id,
-                Name = phone.Name,
-                Price = phone.Price,
-                BrandId = (int)phone.BrandId,
-                Image = phone.Image,
-                Brands = brands
-            };
-            return View(model);
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
         }
         
-        //TODO: Доделать
         [HttpPost]
-        public IActionResult Edit(PhoneCreateViewModel model)
+        public IActionResult Edit(PhoneEditCreateViewModel model)
+        {
+            try
             {
                 if (model is null)
                     return RedirectToAction("Error", "Errors", new {statusCode = 777});
                 string imagePath = string.Empty;
                 if (model.File is null)
                     imagePath = model.Image;
-            
-            _db.Phones.Update(model.MapToPhone(imagePath));
-            _db.SaveChanges();
+                _phoneService.Update(model.MapToPhone(imagePath));
                 return RedirectToAction("Index");
             }
+            catch (EntityNotFoundException e)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 777});
+            }
+            catch (FileNotFoundException)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 666});
+            }
+            catch(Exception)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
+        }
 
         [HttpGet]
         public IActionResult About(int? phoneId)
@@ -147,10 +195,18 @@ namespace PhoneStore.Controllers
                 var phoneViewModel = _phoneService.GetById(phoneId.Value);
                 return View(phoneViewModel);
             }
-            catch (NullReferenceException)
+            catch (EntityNotFoundException e)
             {
                 return RedirectToAction("Error", "Errors", new {statusCode = 777});
             }
+            catch (FileNotFoundException)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 666});
+            }
+            catch(Exception)
+            {
+                return RedirectToAction("Error", "Errors", new {statusCode = 500});
+            }
         }
     }
 }
\ No newline at end of file

PhoneStore/Exceptions/EntityNotFoundException.cs

+using System;
+
+namespace PhoneStore.Exceptions
+{
+    public class EntityNotFoundException : Exception
+    {
+        public EntityNotFoundException(string message)
+            : base(message) { }
+    }
+}
\ No newline at end of file

PhoneStore/Helpers/RepositoryConnector.cs

 using Microsoft.Extensions.DependencyInjection;
+using PhoneStore.Models;
 using PhoneStore.Repositories;
 using PhoneStore.Repositories.Interfaces;
 
@@ -11,6 +12,7 @@ namespace PhoneStore.Helpers
             services.AddScoped<IFeedbackRepository, FeedbackRepository>();
             services.AddScoped<IOrderRepository, OrderRepository>();
             services.AddScoped<IPhoneRepository, PhoneRepository>();
+            services.AddScoped<IBrandRepository, BrandRepository>();
             return services;
         }
     }

PhoneStore/Helpers/ServiceConnector.cs

@@ -26,6 +26,7 @@ namespace PhoneStore.Helpers
             services.AddTransient<IFeedbackService, FeedbackService>();
             services.AddTransient<IPhoneService, PhoneService>();
             services.AddTransient<IOrderService, OrderService>();
+            services.AddTransient<IBrandService, BrandService>();
             return services;
         }
     }

PhoneStore/Mappers/BrandMapper.cs

+using PhoneStore.Models;
+using PhoneStore.ViewModels;
+
+namespace PhoneStore.Mappers
+{
+    public static class BrandMapper
+    {
+        public static BrandViewModel MapToBrandViewModel(this Brand self)
+        {
+            return new BrandViewModel
+            {
+                Id = self.Id,
+                Name = self.Name
+            };
+        }
+        
+        public static Brand MapToBrand(this BrandViewModel self)
+        {
+            return new Brand
+            {
+                Id = self.Id,
+                Name = self.Name
+            };
+        }
+    }
+}
\ No newline at end of file

PhoneStore/Mappers/PhoneMapper.cs

+using System;
 using System.Linq;
+using PhoneStore.Exceptions;
 using PhoneStore.Models;
 using PhoneStore.ViewModels.PhoneViewModels;
 
@@ -6,8 +8,10 @@ namespace PhoneStore.Mappers
 {
     public static class PhoneMapper
     {
-        public static Phone MapToPhone(this PhoneCreateViewModel self, string imagePath = null)
+        public static Phone MapToPhone(this PhoneEditCreateViewModel self, string imagePath = null)
         {
+            if (self is null)
+                throw new EntityNotFoundException("Смартфон не найден");
             Phone phone = new Phone
             {
                 Name = self.Name,
@@ -21,6 +25,9 @@ namespace PhoneStore.Mappers
         }
         public static PhoneViewModel MapToPhoneViewModel(this Phone self)
         {
+            if (self is null)
+                throw new EntityNotFoundException("Смартфон не найден");
+            
             PhoneViewModel phone = new PhoneViewModel
             {
                 Name = self.Name,
@@ -37,6 +44,8 @@ namespace PhoneStore.Mappers
         
         public static Phone MapToPhone(this PhoneViewModel self, string imagePath = null)
         {
+            if (self is null)
+                throw new EntityNotFoundException("Смартфон не найден");
             Phone phone = new Phone
             {
                 Name = self.Name,

PhoneStore/Repositories/BrandRepository.cs

+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using PhoneStore.Models;
+using PhoneStore.Repositories.Interfaces;
+
+namespace PhoneStore.Repositories
+{
+    public class BrandRepository : IBrandRepository
+    {
+        private readonly MobileContext _db;
+
+        public BrandRepository(MobileContext db)
+        {
+            _db = db;
+        }
+
+        public void Create(Brand entity)
+        {
+            _db.Brands.Add(entity);
+            _db.SaveChanges();
+        }
+
+        public async Task CreateAsync(Brand brand)
+        {
+            await _db.Brands.AddAsync(brand);
+            await _db.SaveChangesAsync();
+        }
+
+        public IEnumerable<Brand> GetAll()
+            => _db.Brands;
+
+        public void Update(Brand entity)
+        {
+            _db.Brands.Update(entity);
+            _db.SaveChanges();
+        }
+
+        public Brand GetById(int id)
+        {
+            return _db.Brands.FirstOrDefault(b => b.Id == id);
+        }
+
+        public void Delete(int id)
+        {
+            var brand = _db.Brands.FirstOrDefault(b => b.Id == id);
+            _db.Brands.Remove(brand);
+            _db.SaveChanges();
+        }
+    }
+}
\ No newline at end of file

PhoneStore/Repositories/FeedbackRepository.cs

@@ -23,6 +23,13 @@ namespace PhoneStore.Repositories
                 .First(f => f.Id == id);
         }
 
+        public void Delete(int id)
+        {
+            var feedback = _db.Feedbacks.Find(id);
+            _db.Feedbacks.Remove(feedback);
+            _db.SaveChanges();
+        }
+
         public bool CheckFeedbackExists(int userId, int phoneId)
             => _db.Feedbacks.Any(f => f.UserId == userId && f.PhoneId == phoneId);
 

PhoneStore/Repositories/Interfaces/Base/IBaseOperations.cs

@@ -5,5 +5,6 @@
         void Create(T entity);
         void Update(T entity);
         T GetById(int id);
+        void Delete(int id);
     }
 }
\ No newline at end of file

PhoneStore/Repositories/Interfaces/IBrandRepository.cs

+using System.Collections.Generic;
+using System.Threading.Tasks;
+using PhoneStore.Models;
+using PhoneStore.Repositories.Interfaces.Base;
+
+namespace PhoneStore.Repositories.Interfaces
+{
+    public interface IBrandRepository : IBaseOperations<Brand>
+    {
+        Task CreateAsync(Brand brand);
+        IEnumerable<Brand> GetAll();
+    }
+}
\ No newline at end of file

PhoneStore/Repositories/Interfaces/IPhoneRepository.cs

-using PhoneStore.Models;
+using System.Collections.Generic;
+using PhoneStore.Models;
 using PhoneStore.Repositories.Interfaces.Base;
 
 namespace PhoneStore.Repositories.Interfaces
 {
     public interface IPhoneRepository : IBaseOperations<Phone>
     {
-        
+        IEnumerable<Phone> GetByBrandId(int id);
     }
 }
\ No newline at end of file

PhoneStore/Repositories/OrderRepository.cs

@@ -3,7 +3,6 @@ using System.Linq;
 using Microsoft.EntityFrameworkCore;
 using PhoneStore.Models;
 using PhoneStore.Repositories.Interfaces;
-using PhoneStore.Repositories.Interfaces.Base;
 
 namespace PhoneStore.Repositories
 {
@@ -36,6 +35,13 @@ namespace PhoneStore.Repositories
                 .Include(o => o.User)
                 .FirstOrDefault(o => o.Id == id);
 
+        public void Delete(int id)
+        {
+            var order = _db.Orders.Find(id);
+            _db.Orders.Remove(order);
+            _db.SaveChanges();
+        }
+
         public IEnumerable<Order> GetAll()
         {
             return _db.Orders

PhoneStore/Repositories/PhoneRepository.cs

-using System.Linq;
+using System.Collections.Generic;
+using System.Linq;
 using Microsoft.EntityFrameworkCore;
 using PhoneStore.Models;
 using PhoneStore.Repositories.Interfaces;
@@ -35,5 +36,17 @@ namespace PhoneStore.Repositories
             .FirstOrDefault(p => p.Id == id);
             return a;
         }
+
+        public void Delete(int id)
+        {
+            var phone = _db.Phones.Find(id);
+            _db.Phones.Remove(phone);
+            _db.SaveChanges();
+        }
+
+        public IEnumerable<Phone> GetByBrandId(int id)
+        {
+            return _db.Phones.Where(p => p.BrandId == id);
+        }
     }
 }
\ No newline at end of file

PhoneStore/Services/BrandService.cs

+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using PhoneStore.Mappers;
+using PhoneStore.Models;
+using PhoneStore.Repositories.Interfaces;
+using PhoneStore.Services.Interfaces;
+using PhoneStore.ViewModels;
+
+namespace PhoneStore.Services
+{
+    public class BrandService : IBrandService
+    {
+        private readonly IBrandRepository _brandRepository;
+
+        public BrandService(IBrandRepository brandRepository)
+        {
+            _brandRepository = brandRepository;
+        }
+        public async Task CreateAsync(Brand entity) 
+            => await _brandRepository.CreateAsync(entity);
+
+        public void Delete(int id)
+            => _brandRepository.Delete(id);
+        
+        public IEnumerable<BrandViewModel> GetAll()
+            => _brandRepository.GetAll().Select(x => x.MapToBrandViewModel());
+
+        public void Create(Brand entity)
+            => _brandRepository.Create(entity);
+    }
+}
\ No newline at end of file

PhoneStore/Services/Interfaces/IBrandService.cs

+using System.Collections.Generic;
+using PhoneStore.Models;
+using PhoneStore.ViewModels;
+
+namespace PhoneStore.Services.Interfaces
+{
+    public interface IBrandService : ICreatable<Brand>, IRemovable
+    {
+        IEnumerable<BrandViewModel> GetAll();
+    }
+}
\ No newline at end of file

PhoneStore/Services/Interfaces/ICreateViewModelProvider.cs

+namespace PhoneStore.Services.Interfaces
+{
+    public interface ICreateViewModelProvider<out TViewModel>
+    {
+        TViewModel GetCreateViewModel();
+    }
+}
\ No newline at end of file

PhoneStore/Services/Interfaces/IEditViewModelProvider.cs

+using PhoneStore.ViewModels.PhoneViewModels;
+
+namespace PhoneStore.Services.Interfaces
+{
+    public interface IEditViewModelProvider<out TViewModel>
+    {
+        PhoneEditViewModel GetEditViewModel(int id);
+    }
+}
\ No newline at end of file

PhoneStore/Services/Interfaces/IPhoneService.cs

+using PhoneStore.Models;
+using PhoneStore.ViewModels;
 using PhoneStore.ViewModels.PhoneViewModels;
 
 namespace PhoneStore.Services.Interfaces
 {
-    public interface IPhoneService : ICreatable<PhoneCreateViewModel>
+    public interface IPhoneService : 
+        ICreatable<PhoneCreateViewModel>, 
+        IRemovable, 
+        ICreateViewModelProvider<PhoneEditCreateViewModel>,
+        IEditViewModelProvider<PhoneEditViewModel>
     {
         PhoneViewModel GetById(int phoneId);
+        IndexViewModel GetIndexViewModel (int? brandId);
+        void Update(Phone phone);
     }
 }
\ No newline at end of file

PhoneStore/Services/Interfaces/IRemovable.cs

+namespace PhoneStore.Services.Interfaces
+{
+    public interface IRemovable
+    {
+        void Delete(int id);
+    }
+}
\ No newline at end of file

PhoneStore/Services/PhoneService.cs

 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
@@ -8,6 +9,7 @@ using PhoneStore.Mappers;
 using PhoneStore.Models;
 using PhoneStore.Repositories.Interfaces;
 using PhoneStore.Services.Interfaces;
+using PhoneStore.ViewModels;
 using PhoneStore.ViewModels.Feedback;
 using PhoneStore.ViewModels.PhoneViewModels;
 
@@ -20,6 +22,7 @@ namespace PhoneStore.Services
         private readonly UploadService _uploadService;
         private readonly IHostEnvironment _environment;
         private readonly IPhoneRepository _phoneRepository;
+        private readonly IBrandService _brandService;
 
 
 
@@ -27,13 +30,16 @@ namespace PhoneStore.Services
             MobileContext db, 
             IDefaultPhoneImagePathProvider imagePathProvider, 
             UploadService uploadService, 
-            IHostEnvironment environment, IPhoneRepository phoneRepository)
+            IHostEnvironment environment, 
+            IPhoneRepository phoneRepository,
+            IBrandService brandService)
         {
             _db = db;
             _imagePathProvider = imagePathProvider;
             _uploadService = uploadService;
             _environment = environment;
             _phoneRepository = phoneRepository;
+            _brandService = brandService;
         }
 
         public async Task CreateAsync(PhoneCreateViewModel entity)
@@ -56,14 +62,33 @@ namespace PhoneStore.Services
             await _db.SaveChangesAsync();
         }
 
-        public PhoneViewModel GetById(int phoneId)
+        // public PhoneViewModel GetById(int phoneId)
+        // {
+        //     return _phoneRepository
+        //         .GetById(phoneId)
+        //         .MapToPhoneViewModel();
+        // }
+
+        public IndexViewModel GetIndexViewModel(int? brandId)
+        {
+            IEnumerable<Brand> brands = _db.Brands;
+            IEnumerable<PhoneViewModel> phones = _db.Phones.Select(x => x.MapToPhoneViewModel());
+
+            if (brandId.HasValue)
+                phones = _phoneRepository.GetByBrandId(brandId.Value).Select(x => x.MapToPhoneViewModel());
+            return new IndexViewModel
             {
-            return _phoneRepository
-                .GetById(phoneId)
-                .MapToPhoneViewModel();
+                Brands = brands,
+                Phones = phones
+            };
         }
 
-        public PhoneViewModel GetPhoneById(int phoneId)
+        public void Update(Phone phone)
+        {
+            _phoneRepository.Update(phone);
+        }
+
+        public PhoneViewModel GetById(int phoneId)
         {
             var phone = _db.Phones
                 .Include(p => p.Brand)
@@ -93,5 +118,36 @@ namespace PhoneStore.Services
             };
             return phoneViewModel;
         }
+
+        public void Delete(int id)
+        {
+            _phoneRepository.Delete(id);
+        }
+
+        public PhoneEditCreateViewModel GetCreateViewModel()
+        {
+            PhoneEditCreateViewModel model = new PhoneCreateViewModel
+            {
+                Brands = _brandService.GetAll()
+            };
+            return model;
+        }
+
+        public PhoneEditViewModel GetEditViewModel(int id)
+        {
+            var brands = _brandService.GetAll();
+            var phone = _phoneRepository.GetById(id).MapToPhoneViewModel();
+            
+            PhoneEditViewModel model = new PhoneEditViewModel
+            {
+                Id = phone.Id,
+                Name = phone.Name,
+                Price = phone.Price,
+                BrandId = (int)phone.BrandId,
+                Image = phone.Image,
+                Brands = brands
+            };
+            return model;
+        }
     }
 }
\ No newline at end of file

PhoneStore/ViewModels/BrandViewModel.cs

+namespace PhoneStore.ViewModels
+{
+    public class BrandViewModel
+    {
+        public int Id { get; set; }
+        public string Name { get; set; }
+    }
+}
\ No newline at end of file

PhoneStore/ViewModels/IndexViewModel.cs

 using System.Collections.Generic;
 using PhoneStore.Models;
+using PhoneStore.ViewModels.PhoneViewModels;
 
 namespace PhoneStore.ViewModels
 {
     public class IndexViewModel
     {
-        public IEnumerable<Phone> Phones { get; set; }
+        public IEnumerable<PhoneViewModel> Phones { get; set; }
         public IEnumerable<Brand> Brands { get; set; }
     }
 }
\ No newline at end of file

PhoneStore/ViewModels/PhoneViewModels/PhoneCreateViewModel.cs

-using System.Collections.Generic;
-using System.ComponentModel.DataAnnotations;
-using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.Mvc;
-using PhoneStore.Models;
-
 namespace PhoneStore.ViewModels.PhoneViewModels
 {
-    public class PhoneCreateViewModel : BaseEntity, IPhoneEditable
+    public class PhoneCreateViewModel : PhoneEditCreateViewModel
     {
-        [Required(ErrorMessage = "Поле обязательно для заполнения")]
-        [Remote("CheckName", "PhoneValidator", ErrorMessage = "Имя занято")]
-        [StringLength(50, MinimumLength = 3, ErrorMessage = "Минимальная длина 3 символа, максимальная - 50")]
-        public string Name { get; set; }
-        [Required(ErrorMessage = "Поле обязательно для заполнения")]
-        [Range(1000, 50000, ErrorMessage = "Значение не валидно, вводить можно знаение от 1000 до 5000")]
-        public decimal? Price { get; set; }
-        public int BrandId { get; set; }
-        public List<Brand> Brands { get; set; }
-        public IFormFile File { get; set; }
-        public string Image { get; set; }
+        
     }
 }
\ No newline at end of file

PhoneStore/ViewModels/PhoneViewModels/IPhoneEditable.cs → PhoneStore/ViewModels/PhoneViewModels/PhoneEditCreateViewModel.cs

@@ -2,11 +2,10 @@
 using System.ComponentModel.DataAnnotations;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
-using PhoneStore.Models;
 
 namespace PhoneStore.ViewModels.PhoneViewModels
 {
-    public interface IPhoneEditable
+    public class PhoneEditCreateViewModel
     {
         public int Id { get; set; }
         [Required(ErrorMessage = "Поле обязательно для заполнения")]
@@ -17,7 +16,7 @@ namespace PhoneStore.ViewModels.PhoneViewModels
         [Range(1000, 50000, ErrorMessage = "Значение не валидно, вводить можно знаение от 1000 до 5000")]
         public decimal? Price { get; set; }
         public int BrandId { get; set; }
-        public List<Brand> Brands { get; set; }
+        public IEnumerable<BrandViewModel> Brands { get; set; }
         public IFormFile File { get; set; }
         public string Image { get; set; }
     }

PhoneStore/ViewModels/PhoneViewModels/PhoneEditViewModel.cs

-using System.Collections.Generic;
-using Microsoft.AspNetCore.Http;
-using PhoneStore.Models;
-
-namespace PhoneStore.ViewModels.PhoneViewModels
+namespace PhoneStore.ViewModels.PhoneViewModels
 {
-    public class PhoneEditViewModel : BaseEntity, IPhoneEditable
+    public class PhoneEditViewModel : PhoneEditCreateViewModel
     {
-        public string Name { get; set; }
-        public decimal? Price { get; set; }
-        public int BrandId { get; set; }
-        public List<Brand> Brands { get; set; }
-        public IFormFile File { get; set; }
-        public string Image { get; set; }
     }
 }
\ No newline at end of file

PhoneStore/Views/Phones/Create.cshtml

-@model IPhoneEditable
+@model PhoneEditCreateViewModel
 
 @{
     ViewBag.Title = "title";

PhoneStore/Views/Phones/Delete.cshtml

-@model Phone
+@model PhoneViewModel
 
 @{
     ViewBag.Title = "title";

PhoneStore/Views/Phones/Edit.cshtml

-@model IPhoneEditable
+@model PhoneEditViewModel
 
 @{
     ViewBag.Title = "Редактирование";

PhoneStore/Views/Phones/PartialViews/PhoneFormPartialView.cshtml

-@model PhoneStore.ViewModels.PhoneViewModels.IPhoneEditable
+@model PhoneStore.ViewModels.PhoneViewModels.PhoneEditCreateViewModel
 <div class="mb-3">
     <label asp-for="Name" class="form-label">Наименование</label>
     <input type="text" class="form-control" asp-for="Name">