Non-static method requires a target

Question

I have a controller action that works fine on Firefox both locally and in production, and IE locally, but not IE in production. Here is my controller action:

 public ActionResult MNPurchase()
        {
            CalculationViewModel calculationViewModel = (CalculationViewModel)TempData["calculationViewModel"];

            decimal OP = landTitleUnitOfWork.Sales.Find()
                                            .Where(x => x.Min >= calculationViewModel.SalesPrice)
                                            .FirstOrDefault()
                                            .OP;

            decimal MP = landTitleUnitOfWork.Sales.Find()
                                            .Where(x => x.Min >= calculationViewModel.MortgageAmount)
                                            .FirstOrDefault()
                                            .MP;

            calculationViewModel.LoanAmount = (OP + 100) - MP;
            calculationViewModel.LendersTitleInsurance = (calculationViewModel.LoanAmount + 850);


            return View(calculationViewModel);
        }

Here is the stack trace I get in IE:

Error. An error occurred while processing your request. System.Reflection.TargetException: Non-static method requires a target. at System.Reflection.RuntimeMethodInfo.CheckConsistency(Object target) at System.Reflection.RuntimeMethodInfo.InvokeArgumentsCheck(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, Object[] index) at System.Data.Objects.ELinq.QueryParameterExpression.TryGetFieldOrPropertyValue(MemberExpression me, Object instance, Object& memberValue) at System.Data.Objects.ELinq.QueryParameterExpression.TryEvaluatePath(Expression expression, ConstantExpression& constantExpression) at System.Data.Objects.ELinq.QueryParameterExpression.EvaluateParameter(Object[] arguments) at System.Data.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable1 forMergeOption) at System.Data.Objects.ObjectQuery1.GetResults(Nullable1 forMergeOption) at System.Data.Objects.ObjectQuery1.System.Collections.Generic.IEnumerable.GetEnumerator() at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable1 source) at System.Linq.Queryable.FirstOrDefault[TSource](IQueryable1 source) at LandTitle.Controllers.HomeController.MNRefi() at lambda_method(Closure , ControllerBase , Object[] ) at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary2 parameters) at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary2 parameters) at Castle.Proxies.Invocations.ControllerActionInvoker_InvokeActionMethod.InvokeMethodOnTarget() at Castle.DynamicProxy.AbstractInvocation.Proceed() at Glimpse.Mvc3.Interceptor.InvokeActionMethodInterceptor.Intercept(IInvocation invocation) at Castle.DynamicProxy.AbstractInvocation.Proceed() at Castle.Proxies.AsyncControllerActionInvokerProxy.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass37.<>c__DisplayClass39.b__33() at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass4f.b__49() at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass37.b__36(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass25.<>c__DisplayClass2a.b__20() at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass25.b__22(IAsyncResult asyncResult)

Answer 1

Normally it happens when the target is null. So better check the invoke target first then do the linq query.

Answer 2

All the answers are pointing to a Lambda expression with an NRE (Null Reference Exception). I have found that it also occurs when using Linq to Entities. I thought it would be helpful to point out that this exception is not limited to just an NRE inside a Lambda expression.

Answer 3

I've found this issue to be prevalent in Entity Framework when we instantiate an Entity manually rather than through DBContext which will resolve all the Navigation Properties. If there are Foreign Key references (Navigation Properties) between tables and you use those references in your lambda (e.g. ProductDetail.Products.ID) then that "Products" context remains null if you manually created the Entity.

Answer 4

I face this error on testing WebAPI in Postman tool.

After building the code, If we remove any line (For Example: In my case when I remove one Commented line this error was occur...) in debugging mode then the "Non-static method requires a target" error will occur.

Again, I tried to send the same request. This time code working properly. And I get the response properly in Postman.

I hope it will use to someone...

Answer 5

I think this confusing exception occurs when you use a variable in a lambda which is a null-reference at run-time. In your case, I would check if your variable calculationViewModel is a null-reference.

Something like:

public ActionResult MNPurchase() {
    CalculationViewModel calculationViewModel = (CalculationViewModel)TempData["calculationViewModel"];

    if (calculationViewModel != null) {
        decimal OP = landTitleUnitOfWork.Sales.Find()
                                        .Where(x => x.Min >= calculationViewModel.SalesPrice)
                                        .FirstOrDefault()
                                        .OP;

        decimal MP = landTitleUnitOfWork.Sales.Find()
                                        .Where(x => x.Min >= calculationViewModel.MortgageAmount)
                                        .FirstOrDefault()
                                        .MP;

        calculationViewModel.LoanAmount = (OP + 100) - MP;
        calculationViewModel.LendersTitleInsurance = (calculationViewModel.LoanAmount + 850);


        return View(calculationViewModel);
    } else {
        // Do something else...
    }
}