How to correctly reference ADODB.Recordset type library to resolve "could not find the type library" warning?

[mitaken]

First of all, thank you for providing this great tool.

I have a C# class that creates an ADODB.Recordset and returns it to a COM client. When I build the project, dscom outputs a warning stating that it cannot find the type library for ADODB.Recordset (Warning TX0013116F).

I attempted to resolve this by specifying the type library path using in my .csproj file, but the warning persists.

Could you please guide me on how to correctly reference/embed the ADODB.Recordset type library?

My Environment:

• Target Framework: .NET 10.0 (Windows only)
• ADO Reference: C:\Program Files\Common Files\System\ado\msado15.dll

TestRecordset.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net10.0-windows</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    
    <EnableComHosting>true</EnableComHosting>
    <EnableRegFreeCom>true</EnableRegFreeCom>
    <DsComToolVerbose>true</DsComToolVerbose>
    <DsComTypeLibraryEmbedAfterBuild>true</DsComTypeLibraryEmbedAfterBuild>
  </PropertyGroup>

  <ItemGroup>
    <COMReference Include="ADODB">
      <WrapperTool>tlbimp</WrapperTool>
      <VersionMinor>1</VersionMinor>
      <VersionMajor>6</VersionMajor>
      <Guid>b691e011-1797-432e-907a-4d8c69339129</Guid>
      <Lcid>0</Lcid>
      <Isolated>false</Isolated>
      <EmbedInteropTypes>true</EmbedInteropTypes>
    </COMReference>
  </ItemGroup>

  <ItemGroup>
    <PackageReference Include="dSPACE.Runtime.InteropServices.BuildTasks" Version="2.4.3">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <DsComTlbExportTlbReferences Include="C:\Program Files\Common Files\System\ado\msado15.dll" />
  </ItemGroup>

</Project>

TestRecordset.cs

using ADODB;
using System.Runtime.InteropServices;

namespace TestRecordset
{
    [ComVisible(true)]
    [Guid("7DC55C3B-9A08-4D1D-8022-4578D5C31B44")]
    [InterfaceType(ComInterfaceType.InterfaceIsDual)]
    public interface IRecordsetTlbTest
    {
        [DispId(1)]
        Recordset CreateRecordset();
    }

    [ComVisible(true)]
    [Guid("51B0DAB5-9539-43C4-AA13-F52E346B1539")]
    [ClassInterface(ClassInterfaceType.None)]
    [ProgId("TestRecordset.RecordsetTlbTest")]
    public class RecordsetTlbTest : IRecordsetTlbTest
    {
        public Recordset CreateRecordset()
        {
            return new Recordset();
        }
    }
}

Build log

1>  TestRecordset -> C:\Git\TestRecordset\TestRecordset\bin\Debug\net10.0\TestRecordset.dll
1>  Calling dscom.exe to export type library
1>  Interface 'IRecordsetTlbTest' exported.
1>dscom : warning TX0013116F: Warning: Type library exporter could not find the type library for ADODB.Recordset while writing member TestRecordset.IRecordsetTlbTest.CreateRecordset. IUnknown was substituted for the interface.
1>  Class 'RecordsetTlbTest' exported.
1>  Embedding type library 'C:\Git\TestRecordset\TestRecordset\bin\Debug\net10.0\\TestRecordset.tlb' into assembly 'C:\Git\TestRecordset\TestRecordset\obj\Debug\net10.0\TestRecordset.comhost.dll'...
1>  Calling dscom.exe to embed type library into assembly

[marklechtermann]

The problem here is that DsComTlbExportTlbReferences expects a TLB and not a DLL.
Therefore, you must specify the reference to the tlb of msado15.dll.

See example: https://github.com/dspace-group/dscom?tab=readme-ov-file#example

[mitaken]

Thank you for the suggestion.

I have two points to clarify regarding the situation:

1. About the DLL reference: I originally specified msado15.dll because the Type Library is embedded within this DLL.
2. Result of using the TLB file: Following your advice, I attempted to specify the .tlb file directly as shown below:

<DsComTlbExportTlbReferences Include="C:\Program Files\Common Files\System\ado\msado60.tlb" />

However, the same warning persists, and the issue has not been resolved.

I have created a repository to reproduce this issue.
You can check it here: https://github.com/mitaken/test-recordset

[SOsterbrink]

I'll try to investigate it. I'll get back to you when I understand what is going on here.