DevForce 2010: Object reference not set to an instance of an object

Object reference not set to an instance of an object

Printed From: IdeaBlade
Category: DevForce
Forum Name: DevForce 2010
Forum Discription: For .NET 4.0
URL: http://www.ideablade.com/forum/forum_posts.asp?TID=1822
Printed Date: 21-Apr-2026 at 10:39am

Topic: Object reference not set to an instance of an object

Posted By: GeorgeB
Subject: Object reference not set to an instance of an object
Date Posted: 18-May-2010 at 9:38am

I'm testing a deployment and having a little issue. I'm constantly seeing "Object reference not set to an instance of an object" in the debug logs (this after I get no data back).

This can be seen if I right click on EntityServer.svc in the solution explorerand click on "View in Browser". EntityService.svc however does work.

Now if I run the Silverlight application (locally), it works. If go back to EntityServer.svc , it works.

Below is the stack trace:-

[NullReferenceException: Object reference not set to an instance of an object.]
   IdeaBlade.EntityModel.Server.EntityServerHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) +77
   System.ServiceModel.HostingManager.CreateService(String normalizedVirtualPath) +1440
   System.ServiceModel.HostingManager.ActivateService(String normalizedVirtualPath) +44
   System.ServiceModel.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) +615

[ServiceActivationException: The service '/EntityServer.svc' cannot be activated due to an exception during compilation.  The exception message is: Object reference not set to an instance of an object..]
   System.Runtime.AsyncResult.End(IAsyncResult result) +679246
   System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result) +190
   System.ServiceModel.Activation.HostedHttpRequestAsyncResult.ExecuteSynchronous(HttpApplication context, String routeServiceVirtualPath, Boolean flowContext, Boolean ensureWFService) +234
   System.ServiceModel.Activation.HttpHandler.ProcessRequest(HttpContext context) +24
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +100
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75

George

Replies:

Posted By: kimj
Date Posted: 19-May-2010 at 6:06pm

You will get an exception when browsing to EntityServer.svc if you haven't previously browsed to EntityService.svc. This is because the EntityServer is actually started by the EntityService and expecting it to be there. The exception is unfortunate, but in itself doesn't indicate a problem.

If you're seeing the exception in your application then that does indicate a problem. When your Silverlight application connects, or fetches for the first time if you haven't previously connected, it will first connect to the EntityService, and then the EntityServer. If you're getting the error here, then the debug log should also have more information on why it couldn't start the EntityServer. We do have a bug in 6.0.1 with not using the correct EntityServer URL - see http://www.ideablade.com/forum/forum_posts.asp?TID=1738 - http://www.ideablade.com/forum/forum_posts.asp?TID=1738 . If this looks like the same problem you're having, the workaround in 6.0.1 is to use a ServiceReferences.ClientConfig to define the service endpoints. This issue has been fixed for the 6.0.3 release.

Posted By: GeorgeB
Date Posted: 20-May-2010 at 1:25am

Hi kimj

What happened to 6.0.2? Never saw it.

That makes sense. I'll dig a bit deeper today with the ClientConfig file. I can't use the Globals.asax as I have a seperate WCF service for our backend SAP system. Maybe I just need to double/triple check all the endpoints.

George

Posted By: kimj
Date Posted: 20-May-2010 at 7:18am

Version 6.0.2 was a "beta build" released to only a few customers. Version 6.0.3 is the RTW of DevForce 2010 and will be coming in early June.

Re the globals.asax - do you mean the virtual path provider registration? If so, you can still use this for DevForce services and supply physical .svc files for other services - the virtual path provider will only serve a virtual svc file if a physical one isn't found.

Posted By: GeorgeB
Date Posted: 20-May-2010 at 9:36am

Hi kimj

Oh okay. I'm sure I read somewhere that I couldn't use the globals.asax with other services. My bad.

I'll have a look on Monday when I'm back in the office.

George