Thread: Creating and using a Dll in Dev-C++

Hi all,

This might be a very easy question and a commen topic and I know there is a lot of info on it but I could not find a single tutorial or artical for creating and using a dll in Dev-C++, I am using the latest version 5.0 beta 7 (4.9.7.0). I know there is a project template type dll to select and most of the code is ready but I can't understand it and there is nothing written in the help documents. And the worst part is there is nothing on how to use the compiled dll . The reason why I choose Dev-C++ for my dll is becouse I love it and it is so easy to use, except for this part maybe , and I have already written the program that the dll is for in Dev-C++. I heard on the site www.functionx.com/visualc/applications/staticdll.htm from FunctionX that dlls compiled in Visual C++ can't simply be "plugged" in programs written in Dev-C++ and Borland C++, is that true? And how do I use and create a dll in Dev-C++?

I don't know anything about your specific compiler but I think I can help you with standart mothood:
First the dll. Call it system.dll and write this:

Code:

#include <windows.h>
#include <iostream.h>
#include <stdio.h>

extern "C" __declspec(dllexport) void Hello();
extern "C" __declspec(dllexport) void NumberList(int);

char name[70];

extern "C" __declspec(dllexport) void Hello()
{
  cout << "\nHello from system.dll" << endl;
  cout << endl << endl;
}

extern "C" __declspec(dllexport) void NumberList(int a)
{
	GetModuleFileName(NULL,(LPTSTR)name,70);
	cout << "Called from: " << name << endl << endl;

	int i;
	for (i=a; i<a+10; i++)
	{
		cout << i << "  ";
	}

	cout << endl << endl;
}

This dll will exprot two functions.

Now the main console app:

Code:

  #include <windows.h>
  #include <iostream.h>
  #include <stdio.h>
  #include <conio.h>

  typedef void (*pfunc1)();
  typedef void (*pfunc2)(int);

  pfunc1 One;
  pfunc2 Two; 

int main()
	{	
HINSTANCE hLib = LoadLibrary("system.dll");

  if(hLib==NULL)
	{
	cout << "Error! Can't open dll!";
	return 1;
	}

	char dllpath[70];

	GetModuleFileName((HMODULE)hLib,(LPTSTR)dllpath,70);

	cout << "Dll loaded:" << dllpath << endl;

	One = (pfunc1)GetProcAddress((HMODULE)hLib, "Hello");
	Two = (pfunc2)GetProcAddress((HMODULE)hLib, "NumberList");

	if((One==NULL) || (Two==NULL)) 
	{
	cout << "Critical error! Can't load functions !" << endl;
	FreeLibrary((HMODULE)hLib);
	return 1;
	}

	One();
	Two(50);

	FreeLibrary((HMODULE)hLib);
	getch();

	return 0;
      }

It should work on any compiler. Ask wich line you don't understand.

Thanks for the help but it seems like the new Dev-C++ doesn't include the iostream header and according to the Compiler there must be a DllMain procedure for the Dll and a WinMain for the App, becouse I need other Windows API functions.