Re: Raise Errors from non-coclasses

"Igor Tandetnik" <>
Tue, 4 May 2010 10:43:21 -0400
Barzo <> wrote:

On 4 Mag, 13:43, "Igor Tandetnik" <> wrote:

Barzo wrote:

Ok, now I have to raise a COM error from the non-coclass
implementation file.

AtlReportError, pass GUID_NULL for CLSID parameter.

Like show here:
I use this line to raise an "Invalid Index" to a VB6 client:
return AtlReportError(GUID_NULL, (LPCOLESTR)0, IID_IAudioRecorder,
But the VB6 Err object shows:
Err.Number = -2147352565 (Which is correctly 0x8002000B =
Err.Description = Unknown Error

Hmm. The way AtlReportError (or, to be precise, AtlSetErrorInfo) is =
written, it never sets the description to NULL. If you try to pass NULL =
to it (as you did), it generates a default string "Unknown Error" (as =
you observed).

I suppose you'll have to write your own helper function similar to =
AtlSetErrorInfo. You can look at its implementation in atlcom.h
With best wishes,
    Igor Tandetnik

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necessarily a good idea. It is hard to be sure where they are going to =
land, and it could be dangerous sitting under them as they fly overhead. =
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