Create DLL of a C++ Object

[cdlvj]

Many examples out there but they all show C functions.

Visual .net 2003.
Created a MFC DLL Project (Shared)
Added myDatabase Class with code.
Add the one function that I want to export InsertData

It Builds.
Do I need to add more to this project?
How do I access this from a client?

#pragma once

#include <windows.h>
#include <sqlext.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

class myDatabase
{
private:
	HENV                      hEnv; // Env Handle from SQLAllocEnv()
    HDBC                      hDBC; // Connection handle
	int DBOpen;  

	RETCODE OpenDatabase();
	void doSQLState(HSTMT handle);
    RETCODE CommitDatabase();
	int CloseDatabase();


public:
	myDatabase(void);
	~myDatabase(void);
	int InsertData(char *PID, char *system, char *program, char *step, char *message, char *rc, char *dt);
    
};

; DLLAppLogger.def : Declares the module parameters for the DLL.

LIBRARY      "DLLAppLogger"

EXPORTS
    ; Explicit exports can go here
    	InsertData

 

[cpjust]

InsertData() isn't static, so it requires a this pointer to act on - therefore you can't export it.
You can create a global function to export like this:

int InsertData( myDatabase& thisRef, char *PID, char *system, char *program, char *step, char *message, char *rc, char *dt )
{
   thisRef.InsertData( PID, system, program, step, message, rc, dt );
}

 

[IonelBurtan]

If you need to export something from a DLL look for the __declspec(dllexport) in MSDN. I am sure you'll find something.

Anyway you cannot export a function from a class without exporting the class itself.

But exported classes are just for use in another C++ program because the name of exported functions gets mangled with the C++ sintax (look with depends.exe in the resulting dll to understand what I mean).

HTH,

s-)

Blessed is he who in the name of justice and goodwill, sheperds the weak through the valley of darkness...

http://www20.brinkster.com/ionelb