// This example shows how to subscribe to changes of a single monitored item and display each change.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
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#include "stdafx.h"    // Includes "QuickOpc.h", and other commonly used files
#include <atlcom.h>
#include "SubscribeDataChange.h"

namespace _EasyUAClient
{
    // CEasyUAClientEvents

    class CEasyUAClientEvents : public IDispEventImpl<1, CEasyUAClientEvents>
    {
    public:
    BEGIN_SINK_MAP(CEasyUAClientEvents)
        // Event handlers must have the __stdcall calling convention
        SINK_ENTRY(1, DISPID_EASYUACLIENTEVENTS_DATACHANGENOTIFICATION, &CEasyUAClientEvents::DataChangeNotification)
    END_SINK_MAP()

    public:
        // The handler for EasyUAClient.DataChangeNotification event
        STDMETHOD(DataChangeNotification)(VARIANT varSender, _EasyUADataChangeNotificationEventArgs* pEventArgs)
        {
            // Display the data
            // Remark: Production code would check EventArgsPtr->Exception before accessing EventArgsPtr->AttributeData.
            _UAAttributeDataPtr AttributeDataPtr(pEventArgs->AttributeData);
            _tprintf(_T("%s\n"), (LPCTSTR)CW2CT(AttributeDataPtr->ToString));

            return S_OK;
        }
    };



    void SubscribeDataChange::Main()
    {
        // Initialize the COM library
        CoInitializeEx(NULL, COINIT_MULTITHREADED);
        {
            // Instantiate the client object
            _EasyUAClientPtr ClientPtr(__uuidof(EasyUAClient));

            // Hook events
            CEasyUAClientEvents* pClientEvents = new CEasyUAClientEvents();
            AtlGetObjectSourceInterface(ClientPtr, &pClientEvents->m_libid, &pClientEvents->m_iid, 
                &pClientEvents->m_wMajorVerNum, &pClientEvents->m_wMinorVerNum);
            pClientEvents->m_iid = _uuidof(DEasyUAClientEvents);
            pClientEvents->DispEventAdvise(ClientPtr, &pClientEvents->m_iid);

            //
            _tprintf(_T("Subscribing...\n"));
            ClientPtr->SubscribeDataChange(
                //L"http://opcua.demo-this.com:51211/UA/SampleServer", 
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer",
                L"nsu=http://test.org/UA/Data/ ;i=10853",
                1000);

            _tprintf(_T("Processing monitored item changed events for 1 minute...\n"));
            Sleep(60*1000);

            // Unhook events
            pClientEvents->DispEventUnadvise(ClientPtr, &pClientEvents->m_iid);
        }
         // Release all interface pointers BEFORE calling CoUninitialize()
        CoUninitialize();
    }
}