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ActiveX Control using MFC Extension DLL

I created an ActiveX Control using the ActiveX Control wizard. The control uses a MFC Extension DLL that works with .EXE applications just fine, and has been deployed at customer sites for several months.

The Extension DLL contains several classes that have member functions that return CStrings from the DLLs local stringtable resources. It uses the CString::LoadString() function. This works fine with the .EXE applications, but the ActiveX control does not find the strings in its search through its CDynLinkLibrary chain.

The Extension DLL framework was built by the Extension DLL wizard. I am using VC++ 5.0

It appears that the ActiveX Control OCX is implemented like an Extension DLL and "wires" itself into the chain.

My question is: Why don't the DLL functions find their own resources AND what can be done to correct this?

Modifying the Extension DLL, except to try some things out for debugging, is not a viable option.

Thank you

galkin

First MFC ActiveX controls are implemented as shared DLL not as extension DLL. It is because ActiveX control exports 4 functions to be called by either OLE (DllGetClassObject, DllCanUnloadNow) or by utility(DllRegisterServer, DllUnregisterServer) which are not MFC applications. Extension DLL can be used only with MFC EXE. So ActiveX control doesn't insert itself into resources chain. Since ActiveX control is shared DLL it has its own CWinApp static instance and has its own internal MFC state, like global map of windows handles and objects, resource handle etc.
To allow control to load string from another dll you must supply handle of this DLL for example add hidden property and set it with the handle.

rhgaracci

ASKER

Actually, I figured out the correct answer. I found the solution in Knowledge Base Article Q154126. I modified my extension dll to use the two-step initialization as described in the article (search for words "more recommended" for a description) and called the exported initialization function in the ActiveX control app initialization. This put the extension dll properly in the chain.

Thanks for the reply anyway.

No further responses are requested.

ASKER CERTIFIED SOLUTION

dkremer

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