Polymorphic Extension Visitor with C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace DynamicVisitor
{
    /// <summary>base visitor</summary>
    public class BaseVisitor: VisitorExtension.Visitor
    {
        #region construction and basic framework
        /// <summary>Constructor: the visitor calls Fallback if no matchin Visit method is found.</summary>
        public BaseVisitor()
            : base(false)
        {
        }

        // generic fall back if no visit method is found
        public override void Fallback(object objItem, Exception excException)
        {
            Console.WriteLine("{0}.Fallback({1}, {2})", this.GetType().Name, objItem.GetType().Name, excException.GetType().Name);
        }
        #endregion

        #region User defined Visit methods
        // visit method implementations
        public virtual void Visit(Base objItem)
        {
            Console.WriteLine("BaseVisitor.Visit<Base>({0})", objItem.GetType().Name);
        }
        public virtual void Visit(Derived_A objItem)
        {
            Console.WriteLine("BaseVisitor.Visit<Derived_A>({0})", objItem.GetType().Name);
        }
        #endregion
    }

    /// <summary>specific visitor</summary>
    public class SpecificVisitor : BaseVisitor
    {
        // visit all elements and call the Extension method Accept which calls polymorphically the appropriate Visit method.
        virtual public void Visit(Container objItem)
        {
            Console.WriteLine("SpecificVisitor.Visit<Container>({0})", objItem.GetType().Name);
            foreach (var objElement in objItem.Elements)
            {
                objElement.Accept(this);
            }
        }
    }

}