[解決済み] 値をNULLにすることはできません。パラメータ名：value、CreateIdentityAsync?

質問

ViewModel()を作成しました。 UserModel を実装しています。 IUser<int> (ASP.NET Identity 2.0 カスタマイズ用)

public class UserModel : IUser<int>
{
    public int Id { get; set; }

    public string SecurityStamp { get; set; }

    [Display(Name = "Name")]
    public string FirstName { get; set; }

    [Display(Name = "Last Name")]
    public string LastName { get; set; }

    public string FullName { get; set; }

    [Display(Name = "Username")]
    public string UserName { get; set; }

    [DataType(DataType.Password)]
    [Display(Name = "Password")]
    public string Password { get; set; }

    [Display(Name = "E-Mail")]
    public string Email { get; set; }

    [Display(Name = "Photo")]
    public string PhotoPath { get; set; }

    public List<Claim> Claims { get; set; }

    [IgnoreMapping]
    public List<CommentModel> Comments { get; set; }
}

すべて順調だが GenerateUserIdentityAsync メソッドを使用します。
次のコードは、私の GenerateUserIdentityAsync をUserModelに追加しました。

public async Task<ClaimsIdentity> GenerateUserIdentityAsync(UserManager<UserModel, int> manager)
{
    this.SecurityStamp = Guid.NewGuid().ToString();
    this.Claims = new List<Claim>();

    ClaimsIdentity userIdentity = await manager.CreateIdentityAsync(this, DefaultAuthenticationTypes.ApplicationCookie);//Exception : Value cannot be null. Parameter name: value

    return userIdentity;
}

で例外が発生しました。 CreateIdentityAsync メソッドで、以下のスタックトレースがあります。

ArgumentNullException: Value cannot be null.
Parameter name: value]
   System.Security.Claims.Claim..ctor(String type, String value, String valueType, String issuer, String originalIssuer, ClaimsIdentity subject, String propertyKey, String propertyValue) +10798181
   System.Security.Claims.Claim..ctor(String type, String value) +34
   Microsoft.AspNet.Identity.<CreateAsync>d__0.MoveNext() +1458
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
   System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() +24
   Smartiz.UI.Models.<GenerateUserIdentityAsync>d__2.MoveNext() in e:\Works\Smartiz\Smartiz.UI\Models\UserModels.cs:215
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
   System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() +24
   Smartiz.UI.Controllers.<SignInAsync>d__58.MoveNext() in e:\Works\Smartiz\Smartiz.UI\Controllers\AccountController.cs:448
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
   System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21
   Smartiz.UI.Controllers.<ExternalLoginCallback>d__3c.MoveNext() in e:\Works\Smartiz\Smartiz.UI\Controllers\AccountController.cs:315
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
   System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21
   System.Threading.Tasks.TaskHelpersExtensions.ThrowIfFaulted(Task task) +61
   System.Web.Mvc.Async.TaskAsyncActionDescriptor.EndExecute(IAsyncResult asyncResult) +114
   System.Web.Mvc.Async.<>c__DisplayClass37.<BeginInvokeAsynchronousActionMethod>b__36(IAsyncResult asyncResult) +66
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +47
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +136
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +102
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +49
   System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3d() +117
   System.Web.Mvc.Async.<>c__DisplayClass46.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f() +323
   System.Web.Mvc.Async.<>c__DisplayClass33.<BeginInvokeActionMethodWithFilters>b__32(IAsyncResult asyncResult) +44
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +47
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +136
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +102
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +50
   System.Web.Mvc.Async.<>c__DisplayClass2b.<BeginInvokeAction>b__1c() +72
   System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +185
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +133
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +56
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +40
   System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +34
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +70
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +139
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +59
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +44
   System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller) +39
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +62
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +139
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +59
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +39
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +39
   System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +39
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +70
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +139
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +59
   System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +40
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +38
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9651188
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

私の間違いがどこにあるのか、教えていただけませんか？

解決方法を教えてください。

ASP.NET Identity 1からASP.NET Identity 2へのアップグレード中に同じ問題に直面したが、SecurityStampフィールドにランダムな文字列を入れることによって解決した。

私はこの解決策を見つけました ここで .

あなたにも効果があることを願っています。