dispatch

namespace InvoicesExporter
{
    [ComVisible(true)]
    public class Class1
    {
        Class1()
        {
        }
        public string Hello(string name)
        {
            return "Hello "+ name;
        }

        [ComRegisterFunction()]
        public static void RegisterClass(string key)
        {
            // Strip off HKEY_CLASSES_ROOT\ from the passed key as I don't need it
            StringBuilder sb = new StringBuilder(key);
            sb.Replace(@"HKEY_CLASSES_ROOT\", "");

            // Open the CLSID\{guid} key for write access
            RegistryKey k = Registry.ClassesRoot.OpenSubKey(sb.ToString(), true);

            // And create the 'Control' key - this allows it to show up in
            // the ActiveX control container
            RegistryKey ctrl = k.CreateSubKey("Control");
            ctrl.Close();

            // Next create the CodeBase entry - needed if not string named and GACced.
            RegistryKey inprocServer32 = k.OpenSubKey("InprocServer32", true);
            inprocServer32.SetValue("CodeBase", Assembly.GetExecutingAssembly().CodeBase);
            inprocServer32.Close();

            // Finally close the main key
            k.Close();
        }

        [ComUnregisterFunction()]
        public static void UnregisterClass(string key)
        {
            StringBuilder sb = new StringBuilder(key);
            sb.Replace(@"HKEY_CLASSES_ROOT\", "");

            // Open HKCR\CLSID\{guid} for write access
            RegistryKey k = Registry.ClassesRoot.OpenSubKey(sb.ToString(), true);

            // Delete the 'Control' key, but don't throw an exception if it does not exist
            k.DeleteSubKey("Control", false);

            // Next open up InprocServer32
            RegistryKey inprocServer32 = k.OpenSubKey("InprocServer32", true);

            // And delete the CodeBase key, again not throwing if missing
            k.DeleteSubKey("CodeBase", false);

            // Finally close the main key
            k.Close();
        }
    }
}