calling a WINAPI function from a managed main creates linker error

OK, here is the latest saga from this newbie:

Whenever I try to call EnumDesktopWindows or GetWindowsText the linker vomits out the following:

LocateWindow.obj : error LNK2028: unresolved token (0A00000D) "int __stdcall EnumDesktopWindows(struct HDESK__ *,int (__stdcall*)(struct HWND__ *,long),long)" ( EnumDesktopWindows@@$$J212YGHPAUHDESK__@@P6GHPAUHWND__@@J@ZJ@Z) referenced in function "public: void __thiscall LocateWindow::setPopulateWindowArray(void)" ( setPopulateWindowArray@LocateWindow@@$$FQAEXX

Here is the code: (Yeah, its ugly. I am coming at this slow so I get as much of the concepts down as I can)

// LocateWindow.cpp : main project file.///////////////////////////////////////

#include "stdafx.h"

#include "LocateWindow.h"

//using namespace System;

int main(array<System::String ^> ^args)

{

LocateWindow mainLocateWindow;

mainLocateWindow.PopulateWindowArray();

System::Console::WriteLine(L"Hello World");

return 0;

}

//LocateWindow.h///////////////////////////////////////////////////////////////////

#pragma once

#include <windows.h>

using namespace System::Runtime::InteropServices;

//using namespace System;

static BOOL WINAPI myEnumWindowsHandler(HWND paramTopLevelHandle, LPARAM paramLPARAM){

int functionTest;

LPSTR functionWindowTitle;

functionWindowTitle = new char[MAX_PATH];

functionTest=GetWindowText(paramTopLevelHandle, (LPSTR)functionWindowTitle, MAX_PATH);

if (functionTest){

System::Console::WriteLine(functionWindowTitle);

delete functionWindowTitle;

return true;

}

else{

System::Console::WriteLine("No Title");

delete functionWindowTitle;

return false;

}

};

class LocateWindow{

HDESK classDesktop;

public:

void PopulateWindowArray(){

::EnumDesktopWindows(NULL, myEnumWindowsHandler, (LPARAM)this);

}

};

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calling a WINAPI function from a managed main creates linker error

Scafe
Have you tried linking with user32.lib

Thanks,
Ayman Shoukry
VC++ Team
Mujeeb_rahman
I have looked all through the menus of the IDE, cannot find where to make that link. When I installed the SDK, I made sure the additional dependencies read as follows:

AdditionalDependencies="kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib"

in file corewin_express.vsprops.

The funny thing is I can create a bare bones WIN32 app so it seems my SDK is installed properly :(.
Beaulieu
I just tried your sample code with VC2005 and it worked as expected. Make sure you are linking to User32.lib.

Thanks,
Ayman Shoukry
VC++ Team
SAS8721
Honestly, I am not sure how additional dependencies work. Other folks on the forum might know.

Any ways, I am glad that solved your issue.

Thanks,
Ayman Shoulry
VC++ Team
Michela

Just in case, under the project properties --> linker --> command line, add user32.lib and see if that takes care of the errors.

Thanks,
Ayman Shoukry
VC++ Team
Kajit
OK, here they are:

LocateWindow.obj : error LNK2028: unresolved token (0A00000D) "int __stdcall EnumDesktopWindows(struct HDESK__ *,int (__stdcall*)(struct HWND__ *,long),long)" ( EnumDesktopWindows@@$$J212YGHPAUHDESK__@@P6GHPAUHWND__@@J@ZJ@Z) referenced in function "public: void __thiscall LocateWindow::PopulateWindowArray(void)" ( PopulateWindowArray@LocateWindow@@$$FQAEXXZ)

LocateWindow.obj : error LNK2028: unresolved token (0A000011) "int __stdcall GetWindowTextA(struct HWND__ *,char *,int)" ( GetWindowTextA@@$$J212YGHPAUHWND__@@PADH@Z) referenced in function "int __stdcall `anonymous namespace'::myEnumWindowsHandler(struct HWND__ *,long)" ( myEnumWindowsHandler@ A0x767a8b47@@$$FYGHPAUHWND__@@J@Z)

LocateWindow.obj : error LNK2019: unresolved external symbol "int __stdcall GetWindowTextA(struct HWND__ *,char *,int)" ( GetWindowTextA@@$$J212YGHPAUHWND__@@PADH@Z) referenced in function "int __stdcall `anonymous namespace'::myEnumWindowsHandler(struct HWND__ *,long)" ( myEnumWindowsHandler@ A0x767a8b47@@$$FYGHPAUHWND__@@J@Z)

LocateWindow.obj : error LNK2019: unresolved external symbol "int __stdcall EnumDesktopWindows(struct HDESK__ *,int (__stdcall*)(struct HWND__ *,long),long)" ( EnumDesktopWindows@@$$J212YGHPAUHDESK__@@P6GHPAUHWND__@@J@ZJ@Z) referenced in function "public: void __thiscall LocateWindow::PopulateWindowArray(void)" ( PopulateWindowArray@LocateWindow@@$$FQAEXXZ)
Arul Ram
OK, that worked. Sorry if I was so dense. Have not done any work at the command line, since I normally have had no trouble with the auto settings. But shouldn't the line where I put the additional dependencies in the corewin_.... file have taken care of that
Hamish_NZ

If that is the linker command line, you just need to type in user32.lib. I would also macke sure that is not there already. You can confirm this by looking at the build log.

Thanks,
Ayman Shoukry
VC++ Team
RazzleDazzle
Sorry, haven't messed with the command line functions much. Do have to put a switch in front of it with a / or do I just type in user32.lib
DavidNJ
Hmmm, I use VC2005 as well. I used the app wizard to create the solution. I currently have 2 projects in the solution:

One is a CLR Windows Form. That one compiles and executes great. Until I try to use EnumDesktopWindows, then it goes crazy, complaining during the compile process about me trying to do a _stdcall with the /clr:pure switch.

So I created a second project with a target as a CLR console.

As a CLR console, I can at least create the .obj file, but the linker blows up on it with either link2028 or link2019 errors.
numberonesuperguy
Could you display the exact errors you are seeing

Thanks,
Ayman Shoukry
VC++ Team
calling a WINAPI function from a managed main creates linker error

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