how to write an dll that's used both for c and c++ project.

first, the dll side,write down these code
// DLL Header file...
#ifdef __cplusplus
#define EXPORT extern "C" __declspec(dllexport)
#else
#define EXPORT __declspec(dllexport)
#endif

EXPORT int LoadDialog();

// DLL Implementation file...
EXPORT int LoadDialog()
{
return DialogBox(g_hDllInst, MAKEINTRESOURCE(IDD_DIALOG1), NULL, DlgProc);
}

LRESULT CALLBACK DlgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
...
}

 

then the client side to use it.

// Calling program...
#include <windows.h>

typedef VOID (*MYPROC)(VOID);

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrev, PSTR pCmdLine, int iCmdShow)
{
HMODULE hLib;
MYPROC  theFunc;

hLib = LoadLibrary("dialog.dll");
if (hLib)
{
theFunc = (MYPROC) GetProcAddress(hLib, "LoadDialog");

if (theFunc)
{
theFunc();
}

FreeLibrary(hLib);
return 0;
}


that's all