Illustrated How to do a simple C++ DLL project in Visual Studio ?

Agreed that it isn't a big deal ... however I struggle with this everytime I dip my toes after a long managed stint.. and after a question on stackoverflow - it seems I'm not alone.

So here goes.. Fire up Visual Studio

Ctrl+Shift+N to go to the new project dialog or Right click on the Solution Node - Add - New Project... Press Next instead of Finish to go to the next screen.






So when I do that I have the following structure.
  • Stdafx.h & stdafx.cpp – defines and includes standard header files. Leave unmodified.
  • WinHookFacade_VS2005.cpp – defines the DLL Main function (entry point). Leave unmodified unless you have your very own dllmain.cpp with custom code.
  • Readme.txt – just a text file, you can stuff some info in.


Try to build the project. It should build fine.. do it just to be sure.
Next step include all your .h and .cpp into the project. Right click on the project in solution explorer - Add - Existing item..

You may have build failures.. now its time to enter the maze of C++ Project settings

C++ Settings




If you want additional directories to be looked for resolving header includes. Right click on Project Node - Properties
IMPORTANT: Check the Configuration combobox to read “All Configurations” each time you change a project setting else you risk the debug and release configurations getting out of sync.




Also for some reason, precompiled headers are frowned upon at my workplace. So I turn them off too..



Define any preprocessor symbols you want to.
DETOUR example.. WINHOOKFACADE_EXPORTS is a symbol defined here - which will cause my functions to be exported from here. Referencing projects will not have this symbol defined and will import my functions. The header files begin like this



#ifdef WINHOOKFACADE_EXPORTS
#define WINHOOKFACADE_API __declspec(dllexport)
#else
#define WINHOOKFACADE_API __declspec(dllimport)
#endif

void WINHOOKFACADE_API Hook();


Also in this case, you may want different symbols defined in both configurations. E.g. DEBUG is defined only in Debug configuration and so on.. so change the Configuration Combobox accordingly before making changes.



Linker Settings



To change the default location of the built binary file: E.g. I want the output to be generated in a SolutionDir\bin\Debug or Release. So you can use the helpful macros by pressing the tiny button on the right of the input field
$(SolutionDir)bin\$(ConfigurationName)\$(ProjectName).dll


I also keep the lib files that I need to link to in SolutionDir\bin\lib subfolder. So specify the additional folders to scan for .lib files



To specify the lib files you need to link to...



To specify where the lib file for the current project should be generated. In my case I want it to also go in under SolutionDir\bin\lib and named WinHookFacade_Debug.lib or WinHookFacade_Release.lib
Use the GUI macro helper thingie to come up with your own incantation. In my case it is

$(SolutionDir)bin\lib\$(ProjectName)_$(ConfigurationName).lib





Pre-Post Build steps:
If you’d like to do some tasks (like copying over something) before or after a build, check out the Build events node under Configuration Properties. I’d recommend against using this.. having this in the build script (e.g. ant or nant) makes it more visible – it tends to get hidden and out of sync in the project properties.

Phew! That's it. Take a nap now to recharge those brain cells.

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