Use a static field to count instances

/*
C#: The Complete Reference
by Herbert Schildt

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Use a static field to count instances.

using System;

class CountInst {
static int count = 0;

// increment count when object is created
public CountInst() {
count++;
}

// decrement count when object is destroyed
~CountInst() {
count–;
}

public static int getcount() {
return count;
}
}

public class CountDemo {
public static void Main() {
CountInst ob;

for(int i=0; i < 10; i++) { ob = new CountInst(); Console.WriteLine("Current count: " + CountInst.getcount()); } } } [/csharp]