Unresolved External Symbols - HELP!

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ASKER

Thanks again. I got the linking issues resolved now.

I now have a C++ .NET Class Library Project and when I compile and run it asks what .exe to use for the debug session. what does that mean? Or do I just simply need to compile this into a DLL now and then use it in my other projects? How do I make it a DLL and use it in another project?

I really appreciate your help, is there anything you don't know about this language?

I will up the points for this question if you will help me setup the DLL to be used in another project (C++ is fine for now). I will use this DLL to write a console app which will eventually be replaced by a VB.NET GUI. Thanks again. I am going to keep this question open for the time being so I can raise the point value...

Don

> now have a C++ .NET Class Library Project and when I compile and run it asks what .exe to use for the debug session. what does that mean?
A library cannot run by itself, it does not have a 'main' entry point. It needs to be loaded by another exe.

>Or do I just simply need to compile this into a DLL now and then use it in my other projects? How do I make it a DLL and use it in another project?
As far as I know, a C++ .NET Class Library Project ends up into a dll file. So no need to do anything

Yo use the library in another .NET project, right click on "References" in the client project in Solution Explorer and say "Add Reference...". Then select the "Projects" tab and select the library project. The types defined in the library will now be available to the client project. If the projects are not in the same solution, you'll have to reference the dll directly - use Browse from the .NET tab of the References dialog.

That should read "To use..." instead of "Yo use..."

Of course, a typo....

Do not mind my comment, I thought the typo was mine.
Maybe I should just go home, too much work is not good :o)

ASKER

when I instatiate the class (make the object for use) in the client project, I get:

error C3624: 'System::Object': the compiler cannot find this type; it is defined in the assembly 'mscorlib'

when I click on the error, it send me to the line that I instatiated the object on.

ParametricWedge *pWedge = new ParametricWedge();

Is there something I am missing?

Do you have a
#using <mscorlib.dll>
line?

ASKER

Whoa. I am dumb.

I am still new to this whole .NET structure and "mananged" programming. Thanks.

I have one more question then. When I run the client program I get the following debug error in the middle of execution.

--------------------------------------------------------------------------
An unhandled exception of type 'System.NullReferenceException' occurred in parametricwedge.dll

Additional information: Object reference not set to an instance of an object
--------------------------------------------------------------------------

I assume this is because I forgot to create of instance of an object somewhere. When I set a breakpoint I can see that there are two objects which didnt get initialized inside my DLL. I wonder why the compiler didnt catch this before, but its not important.

How do I creat those objects...they are declared as follows in my class:

--------------------------------------------------------------------------
public __gc struct sCARLOS {
...
}

public __gc struct sEMU {
...
}
--------------------------------------------------------------------------

Then created initiallay as a pointer:
sEMU *EMU;
sCARLOS *CARLOS;

I have tried using:

CARLOS = new sCARLOS;
EMU = new sEMU;

But the compiler in my DLL does not like that very much. Any ideas?

What error do you get. That works when I try it. Is the type visible where youare going the 'new' (have you #included the header)?

Is it sCARLOS and sEMU that are the null references or the internal arrays in thise structures?

ASKER

I got it working now.

Its amazing what actually testing the newer version does, instead of just assuming the same error that was there 1.5 hours ago is still there.

Thanks for the help!

Stator

Hello,

I have the same problem in .

Main App (MFC C++ Project) and a C++ library in one solution, but on the line of a main App where I try to create an instance of a class defined in .dll library:

function_xyz ()
{
// CPPClass is a class defined in a namespace CPPLibrary in a class library project (.dll)

CPPClass instance1 = new CPPClass();
}

i get:

error C2065: 'CPPClass' : undeclared identifier

I added references as described above, ...nothing changed.

Can anyone help ???