How do you raise an error so that VB has it's Err.Number set?

Presently I am using

STDMETHODIMP MyClass::Go()
{
   return Error("Something really bad happened!", IID_IMyClass, 0);

u can use following  code sample which i implemented in my components
Here "SetErrorInfo" function sets the error information object for the
current thread of execution.

HRESULT CError::SetComErrorInfo()
{

START_ERROR_CATCH

 ICreateErrorInfo *pcerrinfo;
 IErrorInfo   *perrinfo;

 HRESULT hResult = CreateErrorInfo( &pcerrinfo );

 pcerrinfo->SetDescription( GetDescription() );
 pcerrinfo->SetHelpContext( GetHelpContext() );
 pcerrinfo->SetHelpFile( GetHelpFile() );

 pcerrinfo->SetSource( GetSource() );

 pcerrinfo->SetGUID( GetGUID() );

 hResult = pcerrinfo->QueryInterface( IID_IErrorInfo, (LPVOID FAR*)
&perrinfo );

 if ( SUCCEEDED( hResult ) )
 {
  SetErrorInfo( 0, perrinfo );
  perrinfo->Release();
   }

   pcerrinfo->Release();

END_ERROR_CATCH

 return m_hErrorCode; // from GetErrorCode();

with best wishes

Arun Devadiga

See AtlReportError() function in MSDN.

There is also an alternative to ATL, called Comet, that allows you to throw
C++ exceptions from your COM components, which automagically get translated
into COM errors -- http://www.lambdasoft.dk/comet/.

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The error should be a negative number - you pass zero = S_OK.
Pass a real failure code there like E_FAIL for example...

--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD

MVP VC FAQ: http://www.mvps.org/vcfaq
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