Re: Interop Prob w/ LPArray - COM Client throwing exception

You use a smart pointer which will call Release after the call
of CoUnitialize(); This can cause an access violation;

Dumitru Sbenghe

> -----Original Message-----
> From: The DOTNET list will be retired 7/1/02
> [mailto:[email protected]]On Behalf Of Aaron Bawcom
> Sent: Monday, June 17, 2002 7:16 AM
> To: [email protected]
> Subject: [DOTNET] Interop Prob w/ LPArray - COM Client throwing
> exception
>
>
> I would appreciate any help/insight that anyone can give on this problem.
> I have a legacy app that uses the following IDL interface definition:
>
> interface IMyInterface2 : IUnknown
> {
>  HRESULT doit( [in, size_is(msgLength)]UCHAR* msg, [in]ULONG
> msgLength );
> };
>
> When my legacy COM Client calls my .Net component that implements this
> interface, an access violation (0xC0000005) exception is thrown. I've
> tried everything and can not figure out why the exception is thrown in the
> COM Client.
>
> Here is the COM Client:
> #include "stdafx.h"
> #include "IMyInterface2_h.h"
> #include "IMyInterface2_i.c"
>
> int _tmain(int argc, _TCHAR* argv[])
> {
>  HRESULT hr = S_OK;
>
>         hr = ::CoInitialize( NULL );
>
>  CLSID rcid = {0};
>  rcid.Data1 = 0x5F850215; rcid.Data2 = 0x7AC2; rcid.Data3 = 0x48b8;
>  rcid.Data4[0] = 0xA8; rcid.Data4[1] = 0xCF; rcid.Data4[2] = 0xA0;
>  rcid.Data4[3] = 0x08; rcid.Data4[4] = 0xF7; rcid.Data4[5] = 0x33;
>  rcid.Data4[6] = 0xD6; rcid.Data4[7] = 0x61;
>
>  CComPtr<IMyInterface2> iMyInterface2;
>
>         hr = iMyInterface2.CoCreateInstance( rcid, NULL,
> CLSCTX_INPROC_SERVER );
>
>  UCHAR* pBytes = (UCHAR*)::CoTaskMemAlloc( 20 );
>
>  ::ZeroMemory( pBytes, 20 );
>
>  iMyInterface2->doit( pBytes, 20 );
>
>  ::CoUninitialize();
>
>  return 0;
> }
>
> And here is the .Net service component. The .Net component must be copied
> in the same directory as the COM client.
>
> using System;
> using System.Runtime.InteropServices;
>
> namespace ComSrv
> {
>  [GuidAttribute("5F850215-7AC2-48b8-A8CF-A008F733D661")]
>  public class MyClass : IMyInterface2
>  {
>   public void doit( byte[] msg, ulong msgLength )
>   {
>   }
>  }
>
>  [ComImport]
>  [GuidAttribute("B55AFAEB-BC7D-4ca9-8065-F9A45FE378B6")]
>  [InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
>  public interface IMyInterface2
>  {
>   void doit(
>    [In, MarshalAs( UnmanagedType.LPArray,
> SizeParamIndex=1, ArraySubType=UnmanagedType.U1 )]byte[] msg,
>    [In]ulong msgLength );
>  }
> }
>
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