Polymorphism/Serialization SoapFormatter (C#)

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.Serialization.Formatters.Soap;
using System.Text;
using System.Xml.Serialization;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {

            // Create a hashtable of values that will eventually be serialized.
            Hashtable dObj = new Hashtable();

            dObj.Add(1,new Line(100, 100));
            dObj.Add(2,new Circle(50, 10, 10));
            dObj.Add(3,new Square(10, 10, 20, 20));
            dObj.Add(4,new DrawingObject());

            Serialize(dObj);
            Hashtable deserializedList = new Hashtable(Deserialize());

            // display the results
            foreach (DrawingObject DrawingObject in deserializedList.Values)
            {
                switch (DrawingObject.GetType().Name)
                {
                    case "Line":
                        Console.WriteLine (string.Format("I'm a {0}", DrawingObject.Draw()) );
                        Line line = (Line)DrawingObject;
                        break;
                    case "Circle":
                        Console.WriteLine (string.Format("I'm a {0}", DrawingObject.Draw()) );
                        Circle circle = (Circle)DrawingObject;
                        break;
                    case "Square":
                        Console.WriteLine (string.Format("I'm a {0}", DrawingObject.Draw()) );
                        Square square = (Square)DrawingObject;
                        break;
                    default:
                        Console.WriteLine (string.Format("I'm just a {0}", DrawingObject.Draw()) );
                        break;
                }
            }

            Console.ReadLine();
        }

        private static void Serialize(Hashtable EmployeeList)
        {

            // Use a file stream here.
            using (FileStream fs = new FileStream("Test.soap", FileMode.Create))
            {
                // Construct a SoapFormatter and use it
                // to serialize the data to the stream.
                SoapFormatter formatter = new SoapFormatter();
                try
                {
                    // Serialize EmployeeList to the file stream
                    formatter.Serialize(fs, EmployeeList);
                }
                catch (Exception e)
                {
                    Console.WriteLine(string.Format("Failed to serialize. Reason: {0}", e.Message));
                }
            }
        }

        private static Hashtable Deserialize()
        {

            // Ctreate the return Hashtable
            Hashtable EmployeeList2=new Hashtable();

            // Open the file containing the data that you want to deserialize.
            using (FileStream fs = new FileStream("Test.soap", FileMode.Open))
            {
                // Construct a SoapFormatter and use it
                // to serialize the data from the stream.
                SoapFormatter formatter = new SoapFormatter();
                try
                {
                    // Deserialize the hashtable from the file
                    EmployeeList2 = (Hashtable)formatter.Deserialize(fs);
                }
                catch (Exception e)
                {
                    Console.WriteLine(string.Format("Failed to serialize. Reason: {0}", e.Message));
                }
            }
            // return the Deserialized data.
            return EmployeeList2;
        }

    }

    // The object we are going to Serializing/De-serializing
    [XmlInclude(typeof(Line))]
    [XmlInclude(typeof(Circle))]
    [XmlInclude(typeof(Square))]
    [Serializable()]
    public class DrawingObject
    {
        public virtual string Draw()
        {
            return "generic drawing object.";
        }
    }

    [Serializable()]
    public class Square : DrawingObject
    {
        public override string Draw()
        {
            return "Square.";
        }

        public Square()
        {
        }

        public Square(int x1, int y1, int x2, int y2)
        {
            X1 = x1;
            Y1 = y1;
            X2 = x2;
            Y2 = y2;
        }

        public int X1 { get; set; }
        public int Y1 { get; set; }

        public int X2 { get; set; }
        public int Y2 { get; set; }
    }

    [Serializable()]
    public class Line : DrawingObject
    {
        public override string Draw()
        {
            return "Line.";
        }

        public Line()
        {
        }

        public Line(int x, int y)
        {
            this.X = x;
            this.Y = y;
        }

        public int X { get; set; }
        public int Y { get; set; }
    }

    [Serializable()]
    public class Circle : DrawingObject
    {
        public override string Draw()
        {
            return "Circle.";
        }

        public Circle()
        {
        }

        public Circle(int radius, int x, int y)
        {
            this.Radius = radius;
            this.X = x;
            this.Y = y;
        }

        public int Radius { get; set; }
        public int X { get; set; }
        public int Y { get; set; }
    }


}