Making My Own DLLs Using C++

Hello World,

Is it possible for anyone to make his own function library
using Turbo C++ and make it available for VB projects?

In fact, i have a serial port communication program which
i wrote in Turbo C++. Thank God it is working, and i want
to use some of its funcs in VB. How can I, if possible?

Thank in advance.

To make a DLL, there are linker options for it. However, you need to tell it what to export. Firstly, the function must use the stdcall calling convention (check your manual - try __stdcall or stdcall), and there must be a .def file. For example:

testdll.cpp

Code:

---

long __stdcall exportfunc(long x) {
    return x * x;
}

---

testdll.def

Code:

---

LIBRARY "TESTDLL.DLL"

EXPORTS
    exportfunc

---

Then, to use in VB, just make a declare for it.