HnD | NullReferenceException at ....LinqUtils.ObtainObjectValuesFromListOfObjects, Page 1

NullReferenceException at ....LinqUtils.ObtainObjectValuesFromListOfObjects

Posts

Robert.W
User

Posts: 79
Joined: 19-Jun-2007

# Posted on: 03-Apr-2010 16:21:22

Here's my scenario:

Using latest runtime libs
asp.net mvc 2
telerik controls for mvc 2

Using telerik mvc grid with ajax binding. Initial load works fine. Subsequent ajax calls for paging / sorting work fine. When i try to filter it fails with the below exception. Let me know if more info is needed.

Controller : [GridAction()] public ActionResult _CustomBinding() { var query = from m in _manufacturerService.GetManufacturersForQuery() select new ManufacturerListItemModel { Id = m.ManufacturerId, Name = m.Name }; return View(new GridModel(query)); }

Manufacturer service:

    public IQueryable<ManufacturerEntity> GetManufacturersForQuery()
    {
        var adapter = _factory.CreateAdapter();
        return new LinqMetaData(adapter).Manufacturer;
    }

Please note that adapter is not disposed until the request end so I don't think its' lifetime is the problem (plus it works fine in other cases I mentioned). Exception is:

[NullReferenceException: Object reference not set to an instance of an object.]
   System.Object.GetType() +0
   SD.LLBLGen.Pro.LinqSupportClasses.LinqUtils.ObtainObjectValuesFromListOfObjects(IList listOfObjects, List`1 listOfFields) +550
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleBinaryExpressionSeparateOperands(BinaryExpression expressionToHandle, Expression leftSide, Expression rightSide) +1493
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleBinaryExpressionBooleanOperator(BinaryExpression expressionToHandle) +138
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +2367
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleDbFunctionCallExpression(DbFunctionCallExpression expressionToHandle) +213
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +447
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleBinaryExpression(BinaryExpression expressionToHandle) +95
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +2431
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleDbFunctionCallExpression(DbFunctionCallExpression expressionToHandle) +213
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +447
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleLikeExpression(LikeExpression expressionToHandle) +95
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +1263
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleBinaryExpressionBooleanOperator(BinaryExpression expressionToHandle) +54
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +2367
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleLambdaExpression(LambdaExpression expressionToHandle) +72
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +2879
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleWhereExpression(WhereExpression expressionToHandle) +215
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +1871
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleAggregateExpression(AggregateExpression expressionToHandle) +73
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.GenericExpressionHandler.HandleExpression(Expression expressionToHandle) +255
   SD.LLBLGen.Pro.LinqSupportClasses.ExpressionHandlers.QueryExpressionBuilder.HandleExpression(Expression expressionToHandle) +214
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProProviderBase.HandleExpressionTree(Expression expression) +724
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProProviderBase.Execute(Expression expression) +16
   SD.LLBLGen.Pro.LinqSupportClasses.LLBLGenProProviderBase.System.Linq.IQueryProvider.Execute(Expression expression) +24
   Telerik.Web.Mvc.Extensions.QueryableExtensions.Count(IQueryable source) +233
   Telerik.Web.Mvc.Extensions.QueryableExtensions.ToGridModel(IQueryable queryable, Int32 page, Int32 pageSize, IList`1 sortDescriptors, IEnumerable`1 filterDescriptors, IEnumerable`1 groupDescriptors) +150
   Telerik.Web.Mvc.UI.GridDataProcessor.EnsureDataSourceIsProcessed() +283
   Telerik.Web.Mvc.GridActionAttribute.OnActionExecuted(ActionExecutedContext filterContext) +326
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +215
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +657347
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +288
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +658084
   System.Web.Mvc.Controller.ExecuteCore() +125
   System.Web.Mvc.&lt;&gt;c__DisplayClass8.&lt;BeginProcessRequest&gt;b__4() +48
   System.Web.Mvc.Async.&lt;&gt;c__DisplayClass1.&lt;MakeVoidDelegate&gt;b__0() +21
   System.Web.Mvc.Async.&lt;&gt;c__DisplayClass8`1.&lt;BeginSynchronous&gt;b__7(IAsyncResult _) +15

   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +85
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +51
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +454
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean&amp; completedSynchronously) +263

Otis
LLBLGen Pro Team

Posts: 39614
Joined: 17-Aug-2003

# Posted on: 04-Apr-2010 12:14:43

enable linq tracing at level 3 (not 4) and rebuild the query in a repro case, and explain the entities involved.

Frans Bouma | Lead developer LLBLGen Pro