How to tell if a file has no associated icon

Question

I am using the SHGetFileInfo api to get a handle to and display the icon associated with a particular file.

If the file has no icon associated with it Windows will return you the default one that it uses in explorer for unknown file types. In this case I don't want to display the icon.

How can I tell if the file has no associated icon and Windows is giving me back the default one?

On my system SHFILEINFO.iIcon is always equal to 3 in this case but i'm not sure how reliable that is and I expect there is a better way to check this.

Edit: I am targeting Windows XP and upwards

Thanks

Answer 1

Which OS versions are you targeting? If you can assume Vista and later, there's an API SHGetStockIconInfo that you may find useful.

SHGetStockIconInfo(SIID_DOCNOASSOC, SHGSI_SYSICONINDEX, &sii)

will return the icon index you're looking for in sii.iSysImageIndex.

Answer 2

You could try passing a fictitious filename with an unknown extension to SHGetFileInfo(), keep track of which icon index it reports, and then compare that index to your real files.