Re: VBS gets empty string

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From: Alexander Nickolov (agnickolov_at_mvps.org)
Date: 07/28/04 

Date: Wed, 28 Jul 2004 10:00:01 -0700

VBScript can only deal with VARIANTs. It cannot get your
BSTR back. Also, you cannot have [out] arguments in
Automation (and VBScript laughs at them all the same).
Change it to [in, out] VARIANT*. Even simpler, why don't
you use [out, retval]? Then you can stick with returning
a BSTR and your server code won't change, only your
script code. As for [in, out], there is a lengthy thread in
this group detailing just that topic, I suggest you give it a
look:

How to return string through output VARIANT from C++
COM object 

-- 
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@mvps.org
MVP VC FAQ: http://www.mvps.org/vcfaq
=====================================
"Eran" <even_e@netvision.net.il> wrote in message
news:e1Yh2QKdEHA.556@tk2msftngp13.phx.gbl...
> Hi,
>
> I need help for the following issue. I have a COM server in C++ and client
> in VBS. in some reason, the VBS gets empty string from COM.
>
> the implemintation is as follows:
>
> [COM]
> [id(4), helpstring("method RetString")] HRESULT ReturnString([out] BSTR
> *RetString);
>
>
> STDMETHODIMP CETS_Interface::ReturnString(BSTR *RetString)
> {
>
>  char MyString[10] = "temp";
>  *RetString = A2BSTR(MyString);
>  return (*RetString != NULL) ? S_OK : E_OUTOFMEMORY;
> }
>
>
> [VBS]
>
>  ' ETS_Interface of "ETS.ETS_Interface.1"
> ' ETS_Interface Class
> Set objETS_Interface = CreateObject("ETS.ETS_Interface")
>
> Dim mystring
>
>  objETS_Interface.RetString(mystring)
> MsgBox(mystring) ' in some reason, I mystring is empty here.
>
>

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