CALL Vb 6 DLL from C#- entry point error

[talktodale]

I am getting the error : Unable to find an entry point named "Myfunc" in DLL "C:\myfunc\my.dll" from the following call from a simple VB 6.0 DLL from C# in VS2005.

This is the code and the steps I have taken.
Visual Basic 6.0 - compile the following as an ActiveX DLL.

Option Explicit
Private Declare Function MyFunc Lib "my.dll" (ByVal cmd As String) As Boolean
Private Sub Command1_Click()
If MyFunc("abc") Then

End If
End Sub



Visual Stuido 2005 - compile and run the following.

using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;

namespace MyFunction
{
class Program
{
[DllImport("c:\\myfunc\\my.DLL")]
public static extern bool MyFunc(string cmd);
public static void Main(string[] args)
{
if (MyFunc("abc"))
{
}
}
}
}

To me, the following error indicates that the my.dll is being loaded okay but it can't find the function.
Here is the error:

An unhandled exception of type 'System.EntryPointNotFoundException' occurred in MyFunction.exe
Additional information: Unable to find an entry point named 'MyFunc' in DLL 'c:\myfunc\my.DLL'.

[abhijit]

Is this a COM DLL? If it was compiled using VB6, it most likely is.
In that case you do not need to resort to the DllImport method.
You need to register the DLL before it can be made available to your projects in C#.

C# lets you add references to COM Dlls.