c++ How to get a COM object Coclass's progid at runtime

Question

I need to write a function that dynamically extracts the progid from a COM object.

Is this possible?

What's the best way to do it?

EDIT: All the coclasses I need to process implement IProvideClassInfo

maybe this is useful: http://stackoverflow.com/questions/1272061/how-to-find-out-a-com-prog-id — Lucian, Nov 13 '12 at 14:07
Thanks, but I didn't find my answer, it's related to c#/.NET — Goldorak84, Nov 13 '12 at 14:29

score 6 · Accepted Answer · answered Nov 13 '12 at 14:32

First of all, there is no guarantee the information is available in first place. Even if you just instantiated an object using ProgID, you might be unale to get it back.

The easiest is to query one of IPersist and friends (IPersistStream etc.) interfaces, and call IPersist::GetClassID to obtain CLSID. Then convert to ProgID using ProgIDFromCLSID or via registry lookup.

Another option is to query IProvideClassInfo and IProvideClassInfo2 to access the CLSID of interest in this alternate way.

The third option, if none of the two above worked, is to query IDispatch and attempt to open type library, then iterate through looking up for coclass information.

Very complete answer! All the objects I needed to process implemented IProvideClassInfo so I used this option to get the CLSID — Goldorak84, Nov 13 '12 at 14:36

c++ How to get a COM object Coclass's progid at runtime

1 Answers1

Linked