Arguments - class

Arguments.cs

var alice = new Person { Name = "Alice", Age = 17 };
Console.WriteLine($"Inside main => {alice.Name}'s age before function call: {alice.Age}");
IncrementAge(alice);
if (alice != null)
{
    Console.WriteLine($"Inside main => {alice.Name}'s age after function call: {alice.Age}");
}
else
{
    Console.WriteLine("Inside main => Object reference not set to an instance of an object");
}            

void IncrementAge(Person person)
{
    Console.WriteLine($"Inside function => {person.Name}'s age before change: {person.Age}");
    person.Age += 1;
    Console.WriteLine($"Inside function => {person.Name}'s age after change: {person.Age}");
    person = null;
}

public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
}