Espresso.NativeV8JsInterOp.RegisterManagedListener C# (CSharp) Method

        static void RegisterManagedListener(ManagedListenerDel mListenerDel)
        {
            RegisterManagedCallback(
                 System.Runtime.InteropServices.Marshal.GetFunctionPointerForDelegate(mListenerDel),
                (int)ManagedCallbackKind.Listener);
        }
       

 public static void RegisterCallBacks()
 {
     //------------------
     //built in listener
     //------------------
     NativeV8JsInterOp.RegisterManagedListener(engineListenerDel);
 }