Thanks for that Pete. It's clear now.

Mark

On Sep 27, 11:16 am, Peter Duniho <NpOeStPe...@NnOwSlPiAnMk.com>
wrote:
[Garbage deleted - just kidding]

This is not the last word however...see below.  Essentially Pete's
example is somewhat trivial, since p=o (identically) and other than as
a placeholder in a loop, most programs need another copy of p.  Below
is an example using a shallow clone, with "p2" being a clone of p
(which is identical with o).  You might also consider a deep clone if
your class inhereits other classes and is complex, since  a shallow
clone references the same objects as the orginal object, which will
result in your clone being deleted if the original object gets
deleted.

RL

////////////////////////
using System;
using System.Collections.Generic;
using System.Text;

namespace mutable
{
   class Program
   {
       static void Main(string[] args)
       {
           MyMutable o = new MyMutable(123);
           MyMutable p = o;
           //MyMutable p2 = (MyMutable)p.Clone(); //gives 123 if
placed here

           o.Value = 456;
           MyMutable p2 = (MyMutable)p.Clone(); //gives 456 when
placed here

           Console.WriteLine("o.Value = {0}", o.Value);
           Console.WriteLine("o.hash is {0}", o.GetHashCode());
           Console.WriteLine("p.Value = {0}", p.Value);
           Console.WriteLine("p.hash is {0}", p.GetHashCode());
//as can be seen when you run this code, p is the very same object as
o
           Console.WriteLine("p2.Value = {0}", p2.Value);
           Console.WriteLine("p2.hash is {0}", p2.GetHashCode());
// as can be seen p2 is a different object than p (and o)

       }
   }
}

/*
// output of above
o.Value = 456
o.hash is 58225482
p.Value = 456
p.hash is 58225482
p2.Value = 456
p2.hash is 54267293
Press any key to continue . . .

*/
////////////////////////////////////////////////////////

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

namespace mutable
{
   class MyMutable : ICloneable
   {
       int _num;

       public MyMutable(int num)
       {
           _num = num;
       }

       public int Value
       {
           get { return _num; }
           set { _num = value; }
       }
       public object Clone()
       {
           return (this.MemberwiseClone()); //shallow clone
       }
   }

}
//////////////