C++, Qt, how do you correctly use Driver functions (dll)?

[Oba22]

There's a COM-port drip to handle the device, with the name "MifareDrv.dll" and the name AddIn.MifareDrv. In fact, there's an example of an OleControl to connect a driver to a business:

uses MifareLib_TLB;
var
Driver: TMifareDrv;
begin
Driver := TMifareDrv.Create(nil);
Driver.Beep;
end;

(even on 1C, but I don't think it's necessary here) When applied to Qt went through QLibrary, the load method confirms that the driver is loaded. Then I decided to check one of the functions as follows.

  typedef void (*Connect) (); 
  Connect con = (Connect)mylib.resolve ("Beep");
  con ();

and does not want to do such a case (compiled, but it falls); and so does any function. In fact, the question is, how do you properly work with the role of the driver? What am I wrong? What other ways can we use?

UPD: Version under Visual C+++

#include "stdafx.h"
#include <windows.h>
#include "Objbase.h"
#import "MifareDrv.tlb" rename_namespace("mifare") // с dll тоже должно работать
CLSID clsid;
mifare::IMifareDrv ;
IDispatch *pWApp;
mifare::IMifareDrv *pMiDrv;
int _tmain(int argc, _TCHAR* argv[])
{
    HRESULT hr = CLSIDFromProgID(L"Addin.MifareDrv", &clsid);
    if (SUCCEEDED(hr))
    {
        LPOLESTR tmpbuf;
        StringFromCLSID(clsid, &tmpbuf);
        CoInitializeEx(NULL, COINIT_MULTITHREADED); // инициализация COM для ридеров
    hr = CoCreateInstance(clsid, NULL, CLSCTX_INPROC_SERVER, IID_IDispatch, (void **)&pWApp);
    hr = pWApp->QueryInterface(__uuidof(mifare::IMifareDrv), (void **)&pMiDrv);
    pMiDrv->PortNumber = 4;
    pMiDrv->Connect();
    pMiDrv->BeepTone = 1;
    pMiDrv->PcdBeep();
}
    return 0;
}

And here's the answer to Qt.

#include <QApplication>
#include <QAxWidget>
QAxWidget *drvFR;
#define CLSID_DrvFR "{450E3DC0-5370-4007-BD5F-90827EC2C2D6}" // это GUID для     объекта драйвера (у меня он звался Addin.MifareDrv). GUID вытащил из регистра 
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
drvFR = new QAxWidget();
drvFR->setControl(CLSID_DrvFR);
drvFR->dynamicCall("FindDevice()");
drvFR->dynamicCall("Connect()");
drvFR->setProperty("BeepTone", 1);
drvFR->dynamicCall("PcdBeep()");
....
и дописать в .pro write QT += axcontainer.

[derk]

Based on Delphi. MifareDrv.dll is the COM library. You're an example. QLibrary You're trying to use it as a normal "baby" DL, which is not right. To use MifareDrv.dll Use basic tools COM From Vijual Studio.

Well, it's easier to show the code. Here's your example for Delphi translated into C+++, Vijual Studio:

// Если не жмет, можно абсолютный путь указать.
// Переименование пространства имен бибилотеки MifareDrv делается
// для того, чтобы точно знать кокое у этого простарнства будет имя
#import "MifareDrv.dll" rename_namespace("mifare") 
CLSID driver_clsid;

if(SUCCEEDED(CLSIDFromProgID(__T("AddIn.MifareDrv"), &driver_clsid))

{

mifare::IMifareDrvPtr driver;

if(SUCCEEDED(driver.CreateInstance(driver_clsid))

{

driver->Beep();

}

}

Directive https://msdn.microsoft.com/en-us/library/8etzzkb6.aspx It specific to C++ from the Visual Studio, it performs the following:

1. Loads the library description file */tlb from the location in question, this example imports DL and file *.tlb is contained as a resource
2. Based on the file received *.tlb generates C+++ headline file with a name <имя библиотеки>.tlh and a name-plate <имя библиотеки>.tli
3. In addition, in the file, *.tlh for each interface found in the library generates a smart indicator statement. https://msdn.microsoft.com/en-us/library/417w8b3b.aspx by name <имя интерфейса>Ptr♪ Like this. IMifareDrvPtr♪

I will like to point out that this example may not be computed because of the fact that it is in the library MifareDrv.dll No interface. IMifareDrv♪ In order to know his exact name, first, read the documentation for the library, second, carefully examine the contents of the generated head restraint. MifareDrv.tlh♪