After Upgrade NuGet-Package to 1.2.20 accessing dynamic properties by index fails

[werner-fleck]

1. Description

After upgrading the NuGet package System.Linq.Dynamic.Core to version 1.2.20, accessing properties of dynamic results by index, i.e. using variable["index"] fails with NullReferenceException. Direct access by property name works, i.e. variable.index.

2. Exception

[NullReferenceException: Object reference not set to an instance of an object.]
   System.Linq.Dynamic.Core.DynamicClass.get_Properties() +125
   CallSite.Target(Closure , CallSite , Object , String ) +181
   MyAppBackend.BusinessLogic.ListManagement.ListManagement.GetListRowId(Nullable`1 listManagementListRowId) in E:\git-repos\MyAppIII\MyAppBackend\BusinessLogic\ListManagement\ListManagement.cs:555
   MyApp.Controllers.ListManagementController.Edit(Nullable`1 listId, Nullable`1 listRowId, Nullable`1 listManagementListRowId) +710
   lambda_method(Closure , ControllerBase , Object[] ) +277
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +34
   System.Web.Mvc.Async.<>c.<BeginInvokeSynchronousActionMethod>b__9_0(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +38
   System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +69
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +41
   System.Web.Mvc.Async.<>c__DisplayClass11_0.<InvokeActionMethodFilterAsynchronouslyRecursive>b__0() +79
   System.Web.Mvc.Async.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +387
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>c__DisplayClass3_6.<BeginInvokeAction>b__4() +50
   System.Web.Mvc.Async.<>c__DisplayClass3_1.<BeginInvokeAction>b__1(IAsyncResult asyncResult) +188
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginExecuteCore>b__152_1(IAsyncResult asyncResult, ExecuteCoreState innerState) +26
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +68
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +52
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +39
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginProcessRequest>b__20_1(IAsyncResult asyncResult, ProcessRequestState innerState) +40
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +68
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +38
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +648
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +213
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +131

3. Fiddle or Project

Our code looks like

            var dc = new DataContext(_connectionString, _xmlMappingSource) {ObjectTrackingEnabled = false};
            var listManagementListRowTable = dc.GetTable(_listManagementListRowType);
            var element = listManagementListRowTable.AsNoTracking().Where("ListManagementListRowId == @0", listManagementListRowId).FirstOrDefault();

            var isDeleted = (bool) element["IsDeleted"];

The exception occurs on the last line.

Using var isDeleted = (bool) element.IsDeleted; instead works.

4. Any further technical details

After downgrading to 1.2.19 our app is working again.

[StefH]

#637