我的 asp.net MVC5 Web 应用程序面临这个问题，使用 Identity v2.0.0.0、EF 6、CaSTLe Windsor IOC 容器、Microsoft SQL Server 2005

我正在尝试使用 UserManagerExtensions,FindById() 方法获取当前登录的用户，但它抛出错误“System.NotSupportedException:第二个操作在上一个异步操作完成之前在此上下文中启动。使用‘await’以确保在此上下文中调用另一个方法之前任何异步操作已完成。不保证任何实例成员都是线程安全的”

我从堆栈跟踪中了解到是“AsyncHelper.RunSync()”导致了问题，我没有在我的代码中使用任何异步函数，而是使用 AsyncHelper 的“FindById()” 引用 -: http://www.symbolsource.org/MyGet/Metadata/aspnetwebstacknightly/Project/Microsoft.AspNet.Identity.Core/2.0.0-beta1-140129/Release/Default/Microsoft.AspNet.Identity.Core/Microsoft.AspNet.Identity.Core/Extensions/UserManagerExtensions.cs?ImageName=Microsoft.AspNet.Identity.Core

关于这个身份错误的信息似乎很少，我在我的应用程序的不同部分使用当前登录用户的详细信息，当调用我的服务层中的 GetCurrentLoggedInUser() 函数时，这个错误似乎是随机发生的。请帮忙....

我的代码和堆栈跟踪如下---- 注意:我在这里发现了另一个类似类型的事件:https://aspnetidentity.codeplex.com/workitem/2408

全局.asax:

        .Register(Component
                    .For<UserManager<ApplicationUser>>()
                    .UsingFactoryMethod((kernel, creationContext) =>
                        new TempoUserManager<ApplicationUser>(new UserStore<ApplicationUser>(new ApplicationDbContext(ASPUserDatabaseConnectionString))))
        .LifestylePerWebRequest()
                    )
        .Register(Component
                    .For<RoleManager<IdentityRole>>()
                    .UsingFactoryMethod((kernel, creationContext) =>
                        new RoleManager<IdentityRole>(new RoleStore<IdentityRole>(new ApplicationDbContext(ASPUserDatabaseConnectionString))))
        .LifestylePerWebRequest()
                    )

服务层代码:

public class GenericService
{
    protected IRepository _repository;
    protected UserManager<ApplicationUser> _userManager;

    public GenericService(IRepository repository, UserManager<ApplicationUser> userManager)
    {
        _repository = repository;
        _userManager = userManager;
    }

    public ApplicationUser GetCurrentLoggedInUser()
    {
        //Error is thrown when calling this
        return _userManager.FindById(HttpContext.Current.User.Identity.GetUserId());
    }
 }

下面是堆栈跟踪，

System.NotSupportedException: A second operation started on this context before a previous asynchronous operation completed. Use 'await' to ensure that any asynchronous operations have completed before calling another method on this context. Any instance members are not guaranteed to be thread safe.
   at System.Data.Entity.Internal.ThrowingMonitor.Enter()
   at System.Data.Entity.Core.Objects.ObjectQuery`1.<GetResultsAsync>d__e.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Internal.LazyAsyncEnumerator`1.<FirstMoveNextAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Infrastructure.IDbAsyncEnumerableExtensions.<FirstOrDefaultAsync>d__25`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   **at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNet.Identity.AsyncHelper.RunSync[TResult](Func`1 func)
   at Microsoft.AspNet.Identity.UserManagerExtensions.FindById[TUser,TKey](UserManager`2 manager, TKey userId)
   at Tempo.BusinessLogics.Services.GenericService.GetCurrentLoggedInUser()
   at Tempo.BusinessLogics.Services.GenericService.GetCurrentLoggedInUserID()
   at Tempo.BusinessLogics.Services.TimeService.UpdateSignOfChildDetails(EntryLog toUpdate, Boolean targetSignState)
   at Tempo.BusinessLogics.Services.TimeService.SignEntries(SignOffs sgnOffs, Byte flag)
   at Tempo.Controllers.TimeEntryController.SignOffAll(String cbxStatus)**
   at lambda_method(Closure , ControllerBase , Object[] )
   at System.Web.Mvc.ActionMethodDispatcher.<>c__DisplayClass1.<WrapVoidAction>b__0(ControllerBase controller, Object[] parameters)
   at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
   at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
   at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass48.<InvokeActionMethodFilterAsynchronouslyRecursive>b__41()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass33.<BeginInvokeActionMethodWithFilters>b__32(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass21.<>c__DisplayClass2b.<BeginInvokeAction>b__1c()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult)
   at System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult)
   at System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult)
   at System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult)
   at System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult)
   at System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result)
   at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

最佳答案

也许您忘记了 await 异步函数，然后下一条语句试图在单个连接上执行两个查询？

关于c# - UserManager 错误 - 在上一个异步操作完成之前在此上下文中启动了第二个操作，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/26351917/