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is there anyone familiar with COM? I met problem when changed project from MFC to Qt

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  • O Offline
    O Offline
    opengpu
    wrote on last edited by
    #11

    CppAPIImp::initialize()
    {
    CreateInstance(__uuidof(DataCOMLib::DataCOM), NULL, CLSCTX_ALL);
    QueryInterface
    FindConnectionPoint
    QueryInterface
    Advise

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    0
    • O Offline
      O Offline
      opengpu
      wrote on last edited by
      #12

      APIImp::release()
      {
      cancelRequest
      Unadvise
      Release

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      0
      • hskoglundH Online
        hskoglundH Online
        hskoglund
        wrote on last edited by
        #13

        Hi, what error do you get from your CoInitializeEx() call? Try something like:

        HRESULT hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
        qDebug() << hr;
        
        
        O 1 Reply Last reply
        2
        • hskoglundH hskoglund

          Hi, what error do you get from your CoInitializeEx() call? Try something like:

          HRESULT hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
          qDebug() << hr;
          
          
          O Offline
          O Offline
          opengpu
          wrote on last edited by
          #14

          @hskoglund that DLL with COM is not Qt program...

          mrjjM 1 Reply Last reply
          0
          • O opengpu

            @hskoglund that DLL with COM is not Qt program...

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #15

            @opengpu
            Hi
            then use std::cout to show the HRESULT.
            It can give hints about why its not loading,.

            What im a bit puzzled about if that is the same DLL used in the MFC app, and you did not change
            the actual DLL code. why should it then stop working?

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            • O Offline
              O Offline
              opengpu
              wrote on last edited by
              #16

              the DLL is the same...
              and i wiil log out the errorcode

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              0
              • O Offline
                O Offline
                opengpu
                wrote on last edited by
                #17

                anyone familiar ?

                mrjjM 1 Reply Last reply
                0
                • O opengpu

                  anyone familiar ?

                  mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by
                  #18

                  @opengpu
                  did you get HRESULT hr out ?

                  O 1 Reply Last reply
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                  • mrjjM mrjj

                    @opengpu
                    did you get HRESULT hr out ?

                    O Offline
                    O Offline
                    opengpu
                    wrote on last edited by
                    #19

                    @mrjj HRESULT = -2147417850

                    mrjjM 1 Reply Last reply
                    0
                    • O opengpu

                      @mrjj HRESULT = -2147417850

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #20

                      @opengpu
                      ok. super. Hopefully mr hskoglund can get something out of that.

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                      0
                      • aha_1980A Offline
                        aha_1980A Offline
                        aha_1980
                        Lifetime Qt Champion
                        wrote on last edited by
                        #21

                        https://en.m.wikipedia.org/wiki/HRESULT describes tools to decode HRESULTs

                        Qt has to stay free or it will die.

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                        • Christian EhrlicherC Offline
                          Christian EhrlicherC Offline
                          Christian Ehrlicher
                          Lifetime Qt Champion
                          wrote on last edited by
                          #22

                          @opengpu said in anyone familiar with COM? i met problem when changed project from MFC to Qt:

                          -2147417850

                          = 0x80010106

                          https://stackoverflow.com/questions/11708497/com-library-initialization-failed-with-code-0x80010106-in-c-sharp

                          "This is a bug in the DLL you are using. A DLL should never call CoInitializeEx() on a thread that it didn't create. "

                          Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                          Visit the Qt Academy at https://academy.qt.io/catalog

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                          • hskoglundH Online
                            hskoglundH Online
                            hskoglund
                            wrote on last edited by
                            #23

                            Hi, what happens to your .DLL if you skip (comment out) the call to CoInitializeEx()?

                            O 1 Reply Last reply
                            0
                            • O Offline
                              O Offline
                              opengpu
                              wrote on last edited by
                              #24

                              0x80010106

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                              0
                              • O Offline
                                O Offline
                                opengpu
                                wrote on last edited by
                                #25
                                This post is deleted!
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                                • O Offline
                                  O Offline
                                  opengpu
                                  wrote on last edited by
                                  #26
                                  #include "stdafx.h"
                                  
                                  BOOL APIENTRY DllMain( HMODULE hModule,
                                                         DWORD  ul_reason_for_call,
                                                         LPVOID lpReserved
                                  					 )
                                  {
                                  	switch (ul_reason_for_call)
                                  	{
                                  	case DLL_PROCESS_ATTACH:
                                  	case DLL_THREAD_ATTACH:
                                  	case DLL_THREAD_DETACH:
                                  	case DLL_PROCESS_DETACH:
                                  		break;
                                  	}
                                  	return TRUE;
                                  }
                                  
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                                  0
                                  • O Offline
                                    O Offline
                                    opengpu
                                    wrote on last edited by
                                    #27
                                    APIImp::APIImp()
                                    {
                                    	//if(!SUCCEEDED(CoInitialize(NULL)))
                                    	HRESULT ret = CoInitializeEx(NULL, COINIT_MULTITHREADED);
                                    	if(!SUCCEEDED(ret))
                                    	{
                                    		//return;
                                    	}
                                    
                                    	initialize();
                                    }
                                    
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                                    0
                                    • hskoglundH hskoglund

                                      Hi, what happens to your .DLL if you skip (comment out) the call to CoInitializeEx()?

                                      O Offline
                                      O Offline
                                      opengpu
                                      wrote on last edited by
                                      #28

                                      @hskoglund why you asked this question?
                                      i didnot return when failed to CoInitializeEx(NULL, COINIT_MULTITHREADED);
                                      it seems worked...

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                                      0
                                      • O Offline
                                        O Offline
                                        opengpu
                                        wrote on last edited by
                                        #29
                                        APIImp::APIImp()
                                        {
                                        	//if(!SUCCEEDED(CoInitialize(NULL)))
                                        	HRESULT ret = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);
                                        	if(!SUCCEEDED(ret))
                                        	{
                                        		return;
                                        	}
                                        
                                        	initialize();
                                        }
                                        

                                        i use COINIT_APARTMENTTHREADED instead of COINIT_MULTITHREADED, and this works fine for me.

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