VC# 2008 interop code not working on VC# 2010

Question

Hi

I am using VS 2010 Express and have ported some code proven in VS 2008 but it fails in VS 2010 and I cannot understand why.

The code uses InvokeMember:

System.Reflection.BindingFlags.InvokeMethod,

null, <Object>.Interface, new object[] { <params> });

It works fine in VS 2008 but not in VS 2010, exception thrown is "Value does not fall within the expected range." The code and references are identical, the <object> is not null.

Baffled.

Any ideas?

Sam Hobbs · Answer

It is common for developers to make assumptions about their software that they are having problems with. I think the primary lesson is to be methodical in diagnosing problems and to verify assumptions whenever possible.

Andy Webster · Answer

Thanks for all the responses. I have now finally discovered that the issue is not as I thought related to the differences between .Net 3.5 VS2008/ .Net 4 VS2010 but an intermittent fault with the network interface card on the development PC causing a failure in the COM interface. It just turns out that the card started to fail at a most unfortunate time ! Having replaced the NIC my code now works fine in both environments without change. We live and learn !

Sam Hobbs · Answer

Then try doing the following just for diagnostic purposes. Try using the VS 2010 debugger to debug the executable built by VS 2008. I am not sure of the details of how to do that; if you need help then say so. I am not sure what that will prove but I think it will help to limit the scope somehow. The thing you need to do is to determine what value it is that it is complaining about but I have no idea how to do that. You still have not made clear what the difference is between the two projects; I assume you have two separate projects for each of VS 2008 and VS 2010. There are other details that would also help that are not provided here.

Andy Webster · Answer

Sam The system is one and the same and is 32 bit. I am opening the VS2008 IDE and executing the code and it works. If I then open the VS2010 IDE and execute the equivalent code it does not work. I have hjad to use coreflags previously for 64 bit systems

Sam Hobbs · Answer

Bit configuration is either 64-bit or 32-bit. Actually for executables there is a third possibility that allows Windows to use either 64-bit or 32-bit depending on the system it is executing in. Which is Windows (64-bit or 32-bit) in the system that the program worked in and in the system it is not working in? Look in the project properties to find the bit configuarion setting; I forget what it is called. What is it? If it is not 32-bit then you probably just need to change it to 32-bit (I think it is called x86).

Andy Webster · Answer

Sam thanks for the response sorry if I offended Regards Andy

Sam Hobbs · Answer

Andy your question does not say very much. First you say it  works fine in VS 2008 but not in VS 2010 . Are you totally sure you are executing it in Visual Studio? Or are you executing it in something built by Visual Studio? It is terminology such as that that can determine whether we can help you. I apologize for saying anything if you truly don't understand the difference but your question is advanced enough that I am sure you do. You say that it worked when you were using VS 2008 but not VS 2010 and you assume there is a difference in VS that causes the problem. That is possible but unlikely. My guess is that there is something else that is different and you are assuming there is not. Suthish suggested the possibility that the bit configuration might be different. If there is anything else that is different then we don't have the information needed to help you. When I said that you  need to use VS to write an application  I was just responding to the question as it was written. You said it works in VS and I said you need to execute it in an application.

Suthish Nair · Answer

Andy Am not sure refer forum . Saying by the bit configuration of project might helps. Or setting a null value to the object.

Andy Webster · Answer

Not a very helpful response. This is a standard approach to calling methods from COM for which there are many examples on many sites. it worked fine and should work fine in VS 2010. I cannot rewrite the code in the COM interface as it is third party and they have not yet released a .Net compliant solution so i have no choice but to attempt to call the methods using the COM interface.

Sam Hobbs · Answer

I am surprised that it works in Visual Studio 2008. You need to use VS to write an application that you port the code to.