caching asp.net

[habbassi869]

hello
i need help please
in this line " if (!_memoryCache.TryGetValue(cacheKey, out ObjWrapper cachedData))" when i test my fonction it shows me System.NullReferenceException : 'La référence d'objet n'est pas définie à une instance d'un objet
memoryCache is null

this is my fonction :
public class HealthCareProfessionalController : BaseController
{
private readonly IMemoryCache _memoryCache;

    public HealthCareProfessionalController()
    {
    }

    public HealthCareProfessionalController(AppUserManager userManager, IMemoryCache memoryCache)
    {
        _userManager = userManager;
        _memoryCache = memoryCache;
    }

    [Authorize(Roles = "PS_Update,HealthCareProfessionalBtn_Create_PS,Menu_SearchHealthCareProfessional")]
    public async Task<ActionResult> PrincipalHealthCareProfessionalForm(int? Id, bool isref = false)
    {
        string cacheKey = Id.HasValue ? "PSData_" + Id.ToString() : "PSData_Null";

        try
        {
            if (!_memoryCache.TryGetValue(cacheKey, out ObjWrapper<ProfessionalHealthViewModel> cachedData))
            {
                try
                {
                    var sw = Stopwatch.StartNew();
                    var vm = new ObjWrapper<ProfessionalHealthViewModel>();
                    var listTasks = new List<Task>();
                    Task<ListWrapper<SelectListItem>> task_DocumentsAgrement = null;
                    Task<ListWrapper<AlerteViewModel>> task_ListAlerte = null;
                    Task<ListWrapper<SelectListItem>> task_DefaultPays = null;

                    using (var client = GetClient())
                    {
                        ViewBag.TypeSaisie = GlobalVariables.TypeDeSaisie;
                        ViewBag.DefaultRegion = ReferencesService.Get(client, "DefaultRegion");

                        var task_TypePS = Task.Run(() => ReferentielsService.GetTypePS(client));
                        listTasks.Add(task_TypePS);

                        var task_TypecategoriesPS = Task.Run(() => ReferentielsService.GetTypeCategoriesPS(client));
                        listTasks.Add(task_TypecategoriesPS);

                        var task_countrySource = Task.Run(() => ReferencesService.Get(client, "Countries"));
                        listTasks.Add(task_countrySource);

                        var task_LanguesCommSource = Task.Run(() => TiersService.GetLanguesComm(client));
                        listTasks.Add(task_LanguesCommSource);

                        var task_PrestationsIntermediaires = Task.Run(() => ReferentielsService.GetPrestationsIntermediaires(client));
                        listTasks.Add(task_PrestationsIntermediaires);

                        if (Id.HasValue)
                        {
                            vm = ReferentielsService.GetPSById(client, Id);
                            if (vm != null && vm.Item != null)
                            {
                                task_DocumentsAgrement = Task.Run(() => ReferentielsService.GetDocumentsAgrementPS(client, Id));
                                listTasks.Add(task_DocumentsAgrement);

                                task_ListAlerte = Task.Run(() => ReferentielsService.GetListAlertePs(client, (int)Id));
                                listTasks.Add(task_ListAlerte);

                                if (vm.Item.Address != null && vm.Item.Address.IdPays != null && vm.Item.Address.IdPays.HasValue)
                                {
                                    // Faites quelque chose avec vm.Item.Address.IdPays
                                }

                                if (ViewBag.TypeSaisie == "domestique")
                                {
                                    task_DefaultPays = Task.Run(() => ReferencesService.Get(client, "DefaultCountry"));
                                    listTasks.Add(task_DefaultPays);

                                    var task_LanguesCommSourceDefault = Task.Run(() => ReferencesService.Get(client, "DefaultLanguage"));
                                    listTasks.Add(task_LanguesCommSourceDefault);
                                }
                            }
                            else
                            {
                                return RedirectToAction("Error500", "Error", new { msg = "PS n'existe pas !!!" });
                            }
                        }
                        else
                        {
                            if (ViewBag.TypeSaisie == "domestique")
                            {
                                task_DefaultPays = Task.Run(() => ReferencesService.Get(client, "DefaultCountry"));
                                listTasks.Add(task_DefaultPays);
                            }
                        }

                        // Exécuter les tâches de manière asynchrone
                        await Task.WhenAll(listTasks.ToArray());

                        // Mettre les données en cache
                        _memoryCache.Set(cacheKey, vm, new MemoryCacheEntryOptions
                        {
                            AbsoluteExpirationRelativeToNow = TimeSpan.FromMinutes(30)
                        });

                        // Vérifier si les tâches ont retourné des listes null et les remplacer par des listes vides
                        ViewBag.DocumentsAgrement = task_DocumentsAgrement?.Result ?? new ListWrapper<SelectListItem>();
                        ViewBag.TypePS = task_TypePS.Result;
                        ViewBag.TypecategoriesPS = task_TypecategoriesPS.Result;
                        ViewBag.countrySource = task_countrySource.Result;
                        ViewBag.LanguesCommSource = task_LanguesCommSource.Result;
                        ViewBag.PrestationsIntermediaires = task_PrestationsIntermediaires.Result;

                        if (ViewBag.TypeSaisie == "domestique")
                        {
                            ViewBag.DefaultPays = task_DefaultPays?.Result ?? new ListWrapper<SelectListItem>();
                        }

                        if (Id.HasValue)
                        {
                            ViewBag.IsEditPS = true;
                            var infos_administratives_PS = Task.Run(() => ReferentielsService.GetInformationsAdministrativesByPS(client, (int)Id));
                            var PS_prestation_intermediaire = Task.Run(() => ReferentielsService.GetPrestationsIntermediairesByPS(client, (int)Id));

                            await Task.WhenAll(infos_administratives_PS, PS_prestation_intermediaire);

                            sw.Stop();

                            vm.Item.infos_administratives_PSViewModel = infos_administratives_PS.Result.Items;
                            vm.Item.PS_prestation_intermediaireViewModel = PS_prestation_intermediaire.Result.Items;

                            ViewBag.time = "( Time taken : " + sw.Elapsed.ToString(@"mm\:ss") + " )";
                            var filename = "PrincipalHealthCareProfessional_TimeTaken_MAI";
                            if (ViewBag.TypeSaisie == "domestique")
                            {
                                filename = "PrincipalHealthCareProfessional_TimeTaken_IGA";
                            }

                            ViewBag.host = CustomViewService.hostname_sagelia;
                            var message = DateTime.Now + ";" + sw.Elapsed.ToString(@"mm\:ss") + ";" + vm.Item.Id + ";" + ViewBag.host;
                            WriteToLogData(message, filename);
                            return View("~/Views/Referentiels/PS/PsForm.cshtml", vm.Item);
                        }
                        else
                        {
                            sw.Stop();
                            ViewBag.time = "( Time taken : " + sw.Elapsed.ToString(@"mm\:ss") + " )";
                            var filename1 = "PrincipalHealthCareProfessional_TimeTaken_MAI";
                            if (ViewBag.TypeSaisie == "domestique")
                            {
                                filename1 = "PrincipalHealthCareProfessional_TimeTaken_IGA";
                            }
                            var vm1 = new ProfessionalHealthViewModel();
                            ViewBag.host = CustomViewService.hostname_sagelia;
                            var message1 = DateTime.Now + ";" + sw.Elapsed.ToString(@"mm\:ss") + ";" + vm1.Id + ";" + ViewBag.host;
                            WriteToLogData(message1, filename1);
                            return View("~/Views/Referentiels/PS/PsForm.cshtml", vm1);
                        }
                    }
                }
                catch (Exception ex)
                {
                    // Gérer les exceptions potentielles ici
                    string errorMessage = $"Une exception s'est produite : {ex.Message}\nStackTrace: {ex.StackTrace}";
                    return RedirectToAction("Error500", "Error", new { msg = errorMessage });

                }
            }
            else
            {
                // Si les données sont déjà dans le cache, utilisez-les directement
                return View("~/Views/Referentiels/PS/PsForm.cshtml", cachedData.Item);
            }
        }
        catch (Exception ex)
        {
            // Gérer les exceptions potentielles ici
            string errorMessage = $"Une exception s'est produite : {ex.Message}\nStackTrace: {ex.StackTrace}";
            return RedirectToAction("Error500", "Error", new { msg = errorMessage });

        }
    }

[LeaFrock]

memoryCache is null

Have you ever injected IMemoryCache? It has nothing to do with the codes you pasted.
You should check if a code line like builder.Services.AddMemoryCache(); exists.