using System;

namespace StaticMembers {

class Person  {

    public static int instances = 0; // static field, it is public for testing purpose only,

    private string name;

    public static string Organisation { get; set; }  // static property

    public int GetInstances( ) {

         return instances;

         }// end GetInstances

​

    public static void WritePersonNumber( ) {

       Console.WriteLine("Using WritePersonNumber, Person Counter is : {0} ", instances);

        }// end WritePersonNumber

       // constructor

    public Person(string name) {

        instances++;

        this.name = name;

         }//end constructor

​

    public string Name  {

        get { return name; }

        set { name = value; }

         }// end Name

   }// end class Person

class PersonTest {

    static void Main( )  {

        Person person1 = new Person("Ahmad");

        Person person2 = new Person("Ziad");

        Person person3 = new Person("Reem");

        Person.Organisation = "Univ.";

        // using the class name (Person) to call the value of instances 

        Console.WriteLine("Using instances, Person Counter is : {0} ", Person.instances);

        // if you use the first object (Person1) to call the value of 

        // instances like this:

        //  Console.WriteLine("Person Counter is : {0} ", person1.instances);

        // you will get the error message: 

        // "Member 'Person1.instances' cannot be accessed with an instance 

        //  reference qualify it with a type name instead

        Person.WritePersonNumber();

       //   person1.WritePersonNumber();// Not accepted 

        Console.WriteLine("Person Organisation is : {0} ", Person.Organisation);

        Console.WriteLine("Person1 Counter is : {0} ", person1.GetInstances());

        Console.WriteLine("Person2 Counter is : {0} ", person2.GetInstances());

        Console.WriteLine("Person3 Counter is : {0} ", person3.GetInstances());

        //  Console.WriteLine("Person Counter is : {0} ", Person.GetInstances()); 

        // Not accepted: you will get the error message: “an object reference is

        // required for the non-static field, method 

        //or property 'Person.GetInstances()”

        Console.ReadKey();

    }// end Main

  }// end class PersonTest

} // end namespace StaticMembers

​