I have a problem calling unmanaged VB COM dll from c#. This is dynamic invocation using loadLibrary and GetProcAddress.

I can successfully loaded the dll using loadLibrary , but the GetProcAddress always return 0. It wasnt log any error msg and nothing. it just returns 0.

below the sample code

VB COM

VERSION 1.0 CLASS
BEGIN
    MultiUse = -1 
    Persistable = 0  
    DataBindingBehavior = 0  
    DataSourceBehavior  = 0 
    MTSTransactionMode  = 0  
END

Attribute VB_Name = "Sample"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = True

Option Explicit

Private Attribute1 As String
Private Sub Class_Initialize()
    Attribute1 = "test"
End Sub

Public Sub TestSub()

End Sub

Public Function testFunction() As String
    testFunction = "default.html"
End Function

Public Function SetData(XML As String) As String
    SetData = Date + Time
End Function

c# code

static class UnManagedInvoker
{
    [DllImport("kernel32.dll")]
    private static extern IntPtr LoadLibrary([MarshalAs(UnmanagedType.LPStr)] string dllToLoad);

    [DllImport("kernel32.dll")]
    private static extern IntPtr GetProcAddress(IntPtr hModule, [MarshalAs(UnmanagedType.LPStr)] string procedureName);

    [DllImport("kernel32.dll")]
    private static extern bool FreeLibrary(IntPtr hModule);

    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
    public delegate string MethodToInvoke(string sdata);

    public static string InvokeUnmanagedDll(string dllPath, string methodName)
    {
        IntPtr DIedDll = LoadLibrary(dllPath);

        IntPtr AddressOfFunction = GetProcAddress(DIedDll, methodName);

        MethodToInvoke MI = (MethodToInvoke)Marshal.GetDelegateForFunctionPointer(AddressOfFunction, typeof(MethodToInvoke));

        string data = MI("ssdasda");

        FreeLibrary(DIedDll);
        return data;

    }
}

And the calling code

 string res = UnManagedInvoker.InvokeUnmanagedDll("xx.dll","SetData");

Can someone help me out..

Update:

I can successfully call the methods if the component is registered. using the below code

Type Med = Type.GetTypeFromCLSID(new Guid("089DD8B0-E12B-439B-B52C-007CA72C93D0"));
object MedObj = Activator.CreateInstance(Med);
object[] parameter = new object[1];
parameter[0] = "asdasd";
var ss = Med.InvokeMember("SetData", System.Reflection.BindingFlags.InvokeMethod, null, MedObj, parameter);

is there a way if the dll not registered.?