C / C++ / MFC

Re: MFC Dll in non-MFC app?

29-Jul-05 10:07

Thanks -- I'll take a look.

Anacreon29-Jul-05 10:27

Re: MFC Dll in non-MFC app?

29-Jul-05 10:27

Well when I put calls to AFX_MANAGE_STATE in, the compiler complains that I have multiple defines of __pRawDllMain and _DllMain@12 -- it is tring to link in dllmodul.obj in mfcs42d.dll and these symbols are defined in my own object code.

By the way, the crash is happening on a worker thread so there is no non-MFC code on the call stack. Don't know if that makes a difference.

Anacreon29-Jul-05 10:44

29-Jul-05 10:44

OK -- I see now that my problem may be, that I don't have a CWinApp-derived class in my DLL -- just a DllMain. I am going to switch over to a CWinApp object and insert the AFX_MANAGE_STATE calls, hopefully that will clear it up.

#include problem

massad29-Jul-05 6:03

massad

29-Jul-05 6:03

This seems like a straightforward problem but I am totally stumped and just can't figure it out. It seems that whenever some changes are made in some of the classes in my project (Specifically a newly added function takes a parameter of a different type class from the Project), the "location" of the include line for that class must be changed inside the "stdafx.h". Otherwise the compiler complains that it does not know what the Object being passed in is.

Here's an example:

[stdafx.h]

#include "class1.h" //the order of files here seems to cause problems.
#include "class2.h"

[class1.h]

#include "stdafx.h"
..... //some code

void Test(Class2* pClass); << //C2061 error occurs on this line saying it does not know what Class2 is!!!!

However if I switched around class2.h to be followed by class1.h in the stdafx.h there would be no problem.

Maybe I am doing something wrong but if I put all the include files into the stdafx.h and them simply include it in every class header file, shouldnt the compiler be able to know what all the classes area?

Any help is greatly appreciated.

Sincerely,

Ilya

John R. Shaw29-Jul-05 6:36

John R. Shaw

29-Jul-05 6:36

massad wrote:
shouldnt the compiler be able to know what all the classes area?

No. The order of the header files can be important. If a prototype in class1.h needs to know about a type defined in class2.h then class2.h normaly needs to be included before class1.h.

Most developers, now days, put a guard define# in there headers so that they will not be included twice (prevents include recursion). This also give you the advantage of allowing you to include any header files (w/guards) in any header file that needs the types defined in that header. It is also why C++ allows you to declare a class type, before it is define.

// class1.h
#ifndef _CLASS1_H_ // guard
#define _CLASS1_H_
#include "class2.h"
class class1 {...}
#endif // _CLASS1_H_

// class1.h
#ifndef _CLASS1_H_ // guard
#define _CLASS1_H_
class class2; // forward declaration
class class1 {...}
#endif // _CLASS1_H_

INTP
"The more help VB provides VB programmers, the more miserable your life as a C++ programmer becomes."
Andrew W. Troelsen

massad29-Jul-05 6:50

massad

29-Jul-05 6:50

Thank you John,

I have fixed the problem. Before I posted here, I tried to use forward declaration and the guards but I still seemed to have the errors appear.

The problem seems to have stemmed from the fact that the code was all inline in the header file (this is the way it was given to me, I didnt write it) and no code was put into the .cpp file.

While trying to figure out what the problem was, I had become fed up with all the code being inline and split it up between a header and the source and the problems disappeared.

Out of curiousity, so that I know for future reference, is there a problem with forward declarations if all the code is inside a header file?

John R. Shaw29-Jul-05 7:07

John R. Shaw

29-Jul-05 7:07

massad wrote:
is there a problem with forward declarations if all the code is inside a header file?

I would not think so. At least I have had no problems, resonantly.

INTP
"The more help VB provides VB programmers, the more miserable your life as a C++ programmer becomes."
Andrew W. Troelsen

Bob Stanneveld29-Jul-05 7:41

Bob Stanneveld

29-Jul-05 7:41

Hello,

It seams that a problem with including to many headers. You should not include stdafx.h in your header.

The problem that you face is that you include stdafx.h in class1.h. In stdafx.h, you include class1.h, which in turn includes stdafx.h again. This is an infinite cycle and the compiler knows this. It just stops including and you get some errors.

If you don't use class1 in class2, you can include class2.h instead of stdafx.h in class1.h and you problem should be gone!

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Anacreon29-Jul-05 7:58

29-Jul-05 7:58

#include "stdafx.h" is a signal to the compiler to use the precompiled header -- your compiler will perform better if you don't include stdafx.h in header files, instead include it as the first include file in your source files.

David Crow29-Jul-05 8:26

David Crow

29-Jul-05 8:26

massad wrote:
[stdafx.h]

#include "class1.h" //the order of files here seems to cause problems.
#include "class2.h"

Why are you including class1.h and class2.h in stdafx.h? In 12 years of using MFC, I've never had the need to include anything in that file except for system (e.g., Win32, MFC, STL) header files.

"One must learn from the bite of the fire to leave it alone." - Native American Proverb

VC++ 2003 NET apps without NET installed?

sunit529-Jul-05 20:48

sunit5

29-Jul-05 20:48

in stdafx.h keep only those header files which are required by every .cpp which will save your compilation time.in your case if u put the header file in stadfx.h the order of these included file is imp as u r using an instance of a class into the other.in ur case its better u dont put up any include file in stadfx.h .rather than u put those header file in the .h file of a .cpp file which u require in that .cpp file

gunrunnerjohn29-Jul-05 5:16

29-Jul-05 5:16

Is there any way to compile a simple console application with Visual Studio NET 2003 to run on a machine without NET Framework installed? I'd like the target application to run on any machine, not just those with NET installed.

I'm sure this is a simple thing, but I sure can't find it! Smile | :)

S. Senthil Kumar29-Jul-05 5:22

S. Senthil Kumar

29-Jul-05 5:22

If you used Managed C++, then no, there is no way you can run those applications without the .NET framework.

Regards
Senthil
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gunrunnerjohn29-Jul-05 5:40

29-Jul-05 5:40

All I want to do is to create a simple console application, I can't believe it's impossible with VC++ NET.

Trollslayer29-Jul-05 12:33

Trollslayer

29-Jul-05 12:33

You will find VC7.1 is there and probably the best solution.

Elaine Rose | [Rose]

The tigress is here Big Grin | :-D

Solved: VC++ 2003 NET apps without NET installed?

GuoChunLiang29-Jul-05 17:14

GuoChunLiang

29-Jul-05 17:14

All I want to do is to create a simple console application, I can't believe it's impossible with VC++ NET.

If a "win32" console application,you can do it.
If a ".NET" console application, you can't do it

Tiny dog is me.

gunrunnerjohn30-Jul-05 7:58

30-Jul-05 7:58

Problem solved, I don't know how the /clr switch got set in the project, but there it is! Smile | :)

McClamm29-Jul-05 5:49

McClamm

29-Jul-05 5:49

I have an option to make a Win32 Console Application in the New Project Wizard, that's close to what you're looking for. You could try making an empty project, too! Just include the basic dependencies you need.

gunrunnerjohn29-Jul-05 7:33

29-Jul-05 7:33

Thanks, I figured it out. I started over with a basic W32 console application. I have no idea why my original attempt refused to function without NET installed, I started it the same way. Confused | :confused:

Judah Gabriel Himango29-Jul-05 8:14

Judah Gabriel Himango

29-Jul-05 8:14

You must've either specified a .NET console project, or turned on managed extensions (/clr switch) in your project settings.

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gunrunnerjohn29-Jul-05 8:30