2016-07-22 0:13 GMT-06:00 Nikolay Sivov bunglehead@gmail.com:
Is it possible we'll need special folder indices here as well? I didn't check thoroughly.
You're right, if the index type is VT_ERROR, FolderItems::Item returns a FolderItem for the containing folder regardless of what the index value is. This special behavior is tested and implemented in v3.
This is assuming you always have VT_I4 on input, but it's obviously possible to call it with any type.
It turns out that FolderItems::Item returns S_OK for VT_I2, V_I4, and V_ERROR, S_FALSE for VT_BSTR, and E_NOTIMPL for everything else. This behavior is tested and implemented in v3.
'dir' is not necessary VT_BSTR.
In v3, Folder::Items returns E_NOTIMPL if dir is VT_I4, the same as Folder::get_Title.
-Alex