How can I run Visual Basic code in a running Visual Basic 6.0 process (e.g. MSVBVM60.DLL)?

I'm working on debugging a legacy Visual Basic 6.0 application; the application was built into native code, but unfortunately we just have the binaries, but no source code. So I'm rather limited as far as modifications to the program go.

My final goal is to get the value of the 'Name' property of some controls given their HWND. I can easily write VisualBasic code to do this, but unfortunately I don't see how to execute this code in the context of the running application.

My first attempt was to create an ActiveX DLL in VisualBasic which exposes my 'controlNameForHWND' function. At runtime, I then had a little utility injected a second helper DLL into the VB running process, and that helper DLL then called CoCreateInstance so that my ActiveX control (which features the 'controlNameForHWND' function开发者_开发技巧 I wrote in VB) is instantiated inside the process of the application.

This worked well, but unfortunately the ActiveX control is apparently not executed in the same context as the application to be debugged. For instance, the global App.hInstance value is different, the array returned by the global Forms array is always empty, and so on. So all my VisualBasic script code is running in a parallel universe. Bad luck. :-/

Does anybody else have ideas how to be able to "inject" VisualBasic code into a VB6 process? Looking at the process using Process Explorer shows that the library MSVBVM60.DLL is loaded (the Microsoft Visual Basic Virtual Machine), but not e.g. VBA.DLL. The latter would be interesting since it exports an undocumented EbExecuteLine function to execute script statements.

I'm running a bit low on ideas, so I'm grateful for the craziest ideas, too. :-)

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A VB6 ActiveX DLL will run in the client process, but it won't have access to the Forms collection of the client process. I think the App.hInstance should return the same value though.

If you are debugging your DLL in the VB6 IDE debugger, that will cause it to run in a separate process. That debugger does some crazy things. You might be better to build a PDB file from the ActiveX DLL and debug in the Visual C++ debugger.