using System;

public class Program

{

    public class CEntity

    {

        public String Entity;

    }

    public class Session

    {

        public CEntity ControlledEntity;

    }

    public static void Main()

    {

        var MySession = new Session();

        if(!(MySession.ControlledEntity is String))

            Console.WriteLine("it works");

        if(MySession.ControlledEntity.Entity is String)

            Console.WriteLine("it works2");

    }

}