Csharp/C Sharp/Collections Data Structure/IComparable

Creates and accesses an array of classes. Implements the IComparable interface

/*
C# Programming Tips & Techniques
by Charles Wright, Kris Jamsa
Publisher: Osborne/McGraw-Hill (December 28, 2001)
ISBN: 0072193794
*/
// ClassArr.cs -- Creates and accesses an array of classes. Implements the
//                IComparable interface.
//
//                Compile this program with the folowing command line
//                    C:>csc ClassArr.cs
//
namespace nsForEach
{
    using System;
    public class ClassArr
    {
        static public void Main ()
        {
             clsElement [] Arr = new clsElement []
                           {
                               new clsElement (8), new clsElement (3),
                               new clsElement (12), new clsElement (7)
                           };
             Console.WriteLine ("Unsorted:");
             foreach (clsElement val in Arr)
             {
                 Console.WriteLine ("The instance number is " + val.Instance);
             }
             Array.Reverse (Arr);
             Console.WriteLine ("\r\nIn Reverse order:");
             foreach (clsElement val in Arr)
             {
                 Console.WriteLine ("The instance number is " + val.Instance);
             }
             Array.Sort (Arr);
             Console.WriteLine ("\r\nSorted:");
             foreach (clsElement val in Arr)
             {
                 Console.WriteLine ("The instance number is " + val.Instance);
             }
             Console.WriteLine ();
        }
    }
    class clsElement : IComparable
    {
        public clsElement (int instance)
        {
            m_Instance = instance;
        }
        private int m_Instance;
        public int Instance
        {
            get{return (m_Instance);}
        }
        public int CompareTo (object o)
        {
            if (o.GetType() != this.GetType())
                throw(new ArgumentException());
            clsElement elem = (clsElement) o;
            return (this.Instance - elem.Instance);
        }
    }
}