using System;

using System.Collections.Generic;

​

public class Person {

    public int? Age {get; set; }

    public int? Height {get; set; }

    public void PrintTextWithPatternMatching() {

        if(this is { Age: null, Height: null}) {

            Console.WriteLine($"All properties are empty");

        }

        else if(this is { Age: null, Height: {}}) {

            Console.WriteLine($"Age is empty, Height: {Height}");

        }

        else if(this is { Age: {}, Height: null}) {

            Console.WriteLine($"Age: {Age}, Height is empty");

        }

        else {

            Console.WriteLine($"Age {Age}, Height: {Height}");

        }

    }

    public void PrintTextOld() {

        if(!Age.HasValue && !Height.HasValue) {

            Console.WriteLine($"All properties are empty");

        }

        else if(!Age.HasValue && Height.HasValue) {

            Console.WriteLine($"Age is empty, Height: {Height}");

        }

        else if(Age.HasValue && !Height.HasValue) {

            Console.WriteLine($"Age: {Age}, Height is empty");

        }

        else {

            Console.WriteLine($"Age {Age}, Height: {Height}");

        }

    }

}

​

public class Program

{

    public static void Main()

    {

        List<Person> persons = new List<Person> { 

            new Person(),

            new Person() { Age = 20 },

            new Person() { Age = null, Height = 160 },

            new Person() { Age = 20, Height = 180 }

        };

        Console.WriteLine("New pattern matching:");

        foreach(var person in persons) {

            person.PrintTextWithPatternMatching();

        }

        Console.WriteLine("\nOld way:");

        foreach(var person in persons) {

            person.PrintTextOld();

        }

    }

}