public class Customer
{
  //Fields, properties, methods and events go here...
}

Customer object1 = new Customer();

Customer object2;

Customer object3 = new Customer();
Customer object4 = object3;

public class Manager : Employee
{
  // Employee fields, properties, methods and events are inherited
  // New Manager fields, properties, methods and events go here...
}

public class Person
{
  // Field
  public string name;

  // Constructor that takes no arguments.
  public Person()
  {
    name = "unknown";
  }

  // Constructor that takes one argument.
  public Person(string nm)
  {
    name = nm;
  }

  // Method
  public void SetName(string newName)
  {
    name = newName;
  }
}
class TestPerson
{
  static void Main()
  {
    // Call the constructor that has no parameters.
    Person person1 = new Person();
    Console.WriteLine(person1.name);

    person1.SetName("John Smith");
    Console.WriteLine(person1.name);

    // Call the constructor that has one parameter.
    Person person2 = new Person("Sarah Jones");
    Console.WriteLine(person2.name);

    // Keep the console window open in debug mode.
    Console.WriteLine("Press any key to exit.");
    Console.ReadKey();
  }
}

unknown
John Smith
Sarah Jones

public class Person
{
  public string Name { get; set; }
  public int Age { get; set; }
  public Person(string name, int age)
  {
    Name = name;
    Age = age;
  }
  //Other properties, methods, events...
}

class Program
{
  static void Main()
  {
    Person person1 = new Person("Leopold", 6);
    Console.WriteLine("person1 Name = {0} Age = {1}", person1.Name, person1.Age);

    // Declare new person, assign person1 to it.
    Person person2 = person1;

    //Change the name of person2, and person1 also changes.
    person2.Name = "Molly";
    person2.Age = 16;

    Console.WriteLine("person2 Name = {0} Age = {1}", person2.Name, person2.Age);
    Console.WriteLine("person1 Name = {0} Age = {1}", person1.Name, person1.Age);

    // Keep the console open in debug mode.
    Console.WriteLine("Press any key to exit.");
    Console.ReadKey();

  }
}

  person1 Name = Leopold Age = 6
  person2 Name = Molly Age = 16
  person1 Name = Molly Age = 16

public struct Person
{
  public string Name;
  public int Age;
  public Person(string name, int age)
  {
    Name = name;
    Age = age;
  }
}

public class Application
{
  static void Main()
  {
    // Create struct instance and initialize by using "new".
    // Memory is allocated on thread stack.
    Person p1 = new Person("Alex", 9);
    Console.WriteLine("p1 Name = {0} Age = {1}", p1.Name, p1.Age);

    // Create new struct object. Note that struct can be initialized
    // without using "new".
    Person p2 = p1;

    // Assign values to p2 members.
    p2.Name = "Spencer";
    p2.Age = 7;
    Console.WriteLine("p2 Name = {0} Age = {1}", p2.Name, p2.Age);

    // p1 values remain unchanged because p2 is copy.
    Console.WriteLine("p1 Name = {0} Age = {1}", p1.Name, p1.Age);

    // Keep the console open in debug mode.
    Console.WriteLine("Press any key to exit.");
    Console.ReadKey();
  }
}

  p1 Name = Alex Age = 9
  p2 Name = Spencer Age = 7
  p1 Name = Alex Age = 9

// Person is defined in the previous example.

//public struct Person
//{
//  public string Name;
//  public int Age;
//  public Person(string name, int age)
//  {
//    Name = name;
//    Age = age;
//  }
//}

Person p1 = new Person("Wallace", 75);
Person p2;
p2.Name = "Wallace";
p2.Age = 75;

if (p2.Equals(p1))
  Console.WriteLine("p2 and p1 have the same values.");

 p2 and p1 have the same values.