用于 vb6 的 C# 和 com

Question

I have an issue with C# and COM.

[Guid("f7d936ba-d816-48d2-9bfc-c18be6873b4d")]
[ComVisible(true)]
[ClassInterface(ClassInterfaceType.None)]
public class Process : IProcess
{

    public Process()
    {
    }

    public int UpdateBalance(string accountNumber, string adminEventDescription, decimal curAmount)
    {
        return 10;
    }
}

[ComVisible(true)]
[Guid("5c640a0f-0dce-47d4-87df-07cee3b9a1f9")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IProcess
{
    int UpdateBalance(string accountNumber, string adminEventDescription, decimal curAmount);
}

And the VB code

Private Sub Command1_Click()
    Dim test As Object
    Set test = New Forwardslash_PlayerTrackingSystem_Api.Process
End Sub

I get the following,

ActiveX component can't create object?

Any ideas on how to fix the issue?

Answer 1

您是否勾选了项目属性中的“注册 COM 互操作”框？

Answer 2

Do you have the ProgID Forwardslash_PlayerTrackingSystem_Api.Process defined in the C# source as well? Your example code does not seem to include it. (Or are you working with an existing type library and creating the object in VB by GUID somehow?)

And is the C# component registered correctly in the registry on the machine where the VB code runs? See the answer by Paolo for a way to have VisualStudio do this for you when you build and/or register it yourself using the regasm.exe tool. This tool is equivalent to regsrv32.exe for "real" COM objects, but then registers an appropriately built .NET assembly in the registry for use from COM.

Answer 3

Your [InterfaceType] attribute is wrong. VB6 requires an IDispatch interface, it cannot handle an IUnknown interface. It likes ComInterfaceType.InterfaceIsDual best, that produces a full type library, enables IntelliSense in the VB6 editor and is roughly a 1000 times faster than the late-bound IDispatch.

Answer 4

如果程序集未在 GAC 中注册，则必须使用regasm的/codebase开关。