在 MVC 4 Web 应用程序中，使用 Mdriven 框架版本是 7.0.12531 来访问来自 SQL 2014 express 的数据。
我们在尝试使用 viewmodel xml（其中包含 OCL）获取数据时遇到错误，错误是（“bughuntinfo internaleval:83 es 似乎fineObject reference not set to an instance of an object.”）
在 Eco.Ocl.Impl.OclImplBase.InternalEvaluate（字符串 oclExpression，IElement rootElement，IClassifier 上下文，SubscriberPairsubscriberPair，IExternalVariableList 变量列表）在 Eco.Ocl.Impl.OclServiceImpl.BaseEvaluate（IElement 根，IClassifier 上下文，IExternalVariableList 变量，字符串表达式）在Eco.Ocl.Impl.OclServiceImpl.Evaluate(IElement root, String expression, IExternalVariableList vars) 在 Eco.ViewModel.Runtime.ViewModelClass.CollectObjectsForCONstraintsCheck(IObjectList allobjects) 在 Eco.ViewModel.Runtime.ViewModel.UpdateErrorsFromConstraints(列表
1 errors, List1 警告，列表1 info, ISubscriber subscriber) at Eco.ViewModel.Runtime.ViewModelClass.ModernQueryPlanExpressionsRunToFindMissing(IElement root, Boolean runallnotsparse, Boolean doStructureNotLevel) at Eco.ViewModel.Runtime.ViewModel.ModernQueryPlanLoop(IFetchConsolidationService fetchconsolidation, Boolean doStructureNotLevel) at Eco.ViewModel.Runtime.ViewModel.ModernQueryPlanExecute(Action doFirstThingInsideQueryPlanAction) at Eco.ViewModel.Runtime.ViewModel.<EnsureSpanFetch>b__42_0() at Eco.Services.Impl.AsyncSupportServiceImpl.WrapTaskInStandardExceptionHandling(Action task) at Eco.Services.Impl.AsyncSupportServiceImpl.PerformTaskNowIfInAsyncThread(Action task) at Eco.ViewModel.Runtime.ViewModel.EnsureSpanFetch() at Eco.ViewModel.Runtime.ViewModel.<>c__DisplayClass156_0.<SetElement>b__0() at Eco.Services.Impl.AsyncSupportServiceImpl.WrapTaskInStandardExceptionHandling(Action task) at Eco.Services.Impl.AsyncSupportServiceImpl.PerformTaskNowIfInAsyncThread(Action task) at Eco.ViewModel.Runtime.ViewModel.SetElement(IEcoObject obj) at Eco.ViewModel.Runtime.ViewModel.set_RootObject(IEcoObject value) at Eco.ViewModel.Runtime.VMClass.UpdateContent(IElement value, Boolean skipCheckOfBeingRoot) at Eco.ViewModel.Runtime.VMClass.set_Content(IElement value) at Eco.ViewModel.Runtime.VMClass..ctor(VMClassDescriptor vMClassDescriptor, IEcoServiceProvider sp, VMClass ownedby, IElement content, IExternalVariableList variables, Boolean useDisplayQueueDrivenAutoPopulate) at Eco.ViewModel.Runtime.VMClassDescriptor.CreateInstance(IEcoServiceProvider sp, IEcoObject iEcoObject, IExternalVariableList iExternalVariableList, Boolean useDisplayQueueDrivenAutoPopulate) at Eco.ViewModel.Runtime.ViewModelHelper.ActOnVMClassFromViewModelRTCreator_WithOptionalVMClassSupplied(VMClass optionalVMClass, VMClassFromViewModelRTCreator x, IEcoObject root, Boolean useDisplayQueueDrivenAutoPopulate) at Eco.ViewModel.Runtime.ViewModelHelper.ActOnVMClassFromViewModelRTCreator(VMClassFromViewModelRTCreator x, IEcoObject root, Boolean useDisplayQueueDrivenAutoPopulate) at Eco.ViewModel.Runtime.ViewModelHelper.CreateFromViewModel(Type esType, EcoSpace es, IEcoObject root, ViewModelRTCreator vmc_c, GetVMClassTypeDelegate creator, IViewUICreator externalViewUICreator, Action1 initViewModelAction, Boolean useDisplayQueueDrivenAutoPopulate, IEcoServiceProvider spToUse) 在 Eco.ViewModel.Runtime.ViewModelHelper.CreateFromViewModel(Type esType, EcoSpace es, IEcoObject root, ViewModelRTCreator vmc_c, GetVMClassTypeDelegate creator, Boolean useDisplayQueueDrivenAutoPopulate, IEcoServiceProvider spToUse) 在 Eco.ViewModel.Runtime.ViewModelHelper。在 Eco.ViewModel.Runtime.ViewModelHelper.CreateFromViewModel(String viewmodelName, EcoSpace es, IEcoObject root, GetVMClassTypeDelegate creator, Boolean useDisplayQueueDrivenAutoPopulate) 在 Eco.ViewModel.Runtime 的 CreateFromViewModel(EcoSpace es, IEcoObject root, ViewModelRTCreator vmc_c, GetVMClassTypeDelegate creator, Boolean useDisplayQueueDrivenAutoPopulate)。 ViewModelHelper.CreateFromViewModel(String viewmodelName, EcoSpace es, IEcoObject root)
