static void Main(string[] args) { // new person objects Person person1 = new Person { Firstname = "Kirsi", Lastname = "Mainio", SocialSecurityNumber = "112212-1212" }; Person person2 = new Person { Firstname = "Salla", Lastname = "Aalto", SocialSecurityNumber = "113313-1313" }; Person person3 = new Person { Firstname = "Timo", Lastname = "Laine", SocialSecurityNumber = "114414-1414" }; Person person4 = new Person { Firstname = "Kalle", Lastname = "Kovis", SocialSecurityNumber = "115515-1515" }; // create a Persons object Persons myFriends = new Persons(); // add person objects to persons collection myFriends.AddPerson(person1); myFriends.AddPerson(person2); myFriends.AddPerson(person3); myFriends.AddPerson(person4); // get one person from Persons collection Person person5 = myFriends.GetPerson(5); if (person5 != null) { Console.WriteLine(person5.ToString()); } else { Console.WriteLine("Person not found in that index!"); } // print collection myFriends.PrintCollection(); // find person string sotu = "114414-1416"; Console.WriteLine("Find sotu : " + sotu); Person person6 = myFriends.FindPerson(sotu); if (person6 != null) { Console.WriteLine(person6.ToString()); } else { Console.WriteLine("Can't find person with that sotu..."); } }