I'm sure this has probably been asked before ....
I have rewritten a COM DLL into C#, with a number of interface
functions, and a number of events that can be fired back to the
client(s). I can call it from a VB (6) client without problems.
However, when I try to use a C++ client (still visual studio 6) that
worked with the old DLL, any call to an interface function gets the
error "The value of ESP was not properly saved across a function
call."
A couple of example functions would be :
(C#)
int DialDigits([MarshalAs(UnmanagedType.BStr)]string bsUserId,
[MarshalAs(UnmanagedType.BStr)]string szDigits);
int QueryStatusString([MarshalAs(UnmanagedType.BStr)] ref
string pbsStatus);
(C++)
m_pInterface->DialDigits(_bstr_t("1001").copy(),
_bstr_t("01234567890").copy());
BSTR bsError;
if ( m_pTapi->QueryStatusString( &bsError ) == S_OK ) ....
Both of these function calls get the same error.
The VB client doesn't seem to care whether the C# parameters are
marshalled or not, they just works, but I added the marshalling as
hinted by some other web site, but that didn't help in this C++ case.
Is there anything wrong with either my C#' interface definition, or is
something special required in order to call a .NET COM dll from
unmanaged code ?
I can post the full interface if necessary, but it is a big lengthy.
I actually converted the IDL to C# by hand, but when it worked from
VB, I assumed I'd got it all right, but now I'm not so sure. Can
anyone help ?
- Tim
--
You received this message because you are subscribed to the Google
Groups "DotNetDevelopment, VB.NET, C# .NET, ADO.NET, ASP.NET, XML, XML
Web Services,.NET Remoting" group.
To post to this group, send email to dotnetdevelopment@googlegroups.com
To unsubscribe from this group, send email to
dotnetdevelopment+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/dotnetdevelopment?hl=en?hl=en
or visit the group website at http://megasolutions.net
