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Can I improve my .NET COM object to catch usage errors at compile time in VB6

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Last Modified: 2020-01-01
For some time now I've been writing C# COM visible DLLs for use in an old VB6 application.

I've recently become aware that my COM visible class isn't browsable in the Object Browser nor does the IDE catch compile-time errors. Here's a sample interface and class:
namespace Sample
{
    [Guid("FDB56085-E1C2-41E3-8B6A-86F734B9338B")]
    public interface ITest
    {
        #region Methods

        void Foo();
        void Bar();

        #endregion
    }
    [ComVisible(true)]
    [ClassInterface(ClassInterfaceType.None)]
    [Guid("6717C7FC-9E3F-47A1-955C-09734F96B18F")]
    public class Test: ITest
    {
        #region Public Methods

        public void Foo()
        {

        }

        public void Bar()
        {

        }

        #endregion
    }
}

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All this compiles fine and any code I insert into Foo() or Bar() will execute without a problem. However, I can also do this in VB6:
    Dim tAs Sample.Test
    t.Foo
    t.Bar
    t.CompileError

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and the compiler doesn't complain at all. At runtime the last line does generate an error indicating that the method is not implemented but nothing at compile time. Also, the entire class is not browsable in the Object Browser. I can live with the 2nd part but I'm hoping there's a way to force the compiler to catch such errors during compilation. Any suggestions?
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