Don't kwow how to retrieve properties from objects declared as abstract class type in C#

Question

I’m learning C# and I have a doubt about the use of inheritance in classes and I would like that somebody could help me.

If I have some classes that inherit from a abstract class, I can declare an object of the secondary class as of the type of the primary abstract class, like this:

Animal leopard = new Mammal();

Where Mammal is a class that inherit from the abstract class Animal. In this case, how can I access the properties that are exclusively from Mammal class? Look the following code for a better understanding:

        static void Main(string[] args)
        {
            Animal leopard = new Mammal("leopard", "mammal", "yellow", 80);
            Bird falcon = new Bird("falcon", "bird", "black", 300);
            Fish shark = new Fish("shark", "fish", "white", 80);
            List<Animal> animalList = new List<Animal>();            

            animalList.Add(leopard);
            animalList.Add(falcon);
            animalList.Add(shark);

            Console.WriteLine("Name: {0}, Class: {1}, Fur Collor: {2}, Running Speed: {3} km/h.",
                leopard.name, leopard.animalClass, leopard.furColor, leopard.runningSpeed);
            
            Console.ReadLine();
        }

        public abstract class Animal
        {
            public string name { get; set; }
            public string animalClass { get; set; }
        }

        public class Mammal : Animal
        {
            public string furColor { get; set; }
            public double runningSpeed { get; set; }

            public Mammal(string name, string animalClass,
                string furColor, double runningSpeed)
            {
                this.name = name;
                this.animalClass = animalClass;
                this.furColor = furColor;
                this.runningSpeed = runningSpeed;
            }
        }

        public class Bird : Animal
        {
            public string featherColor { get; set; }
            public double flightSpeed { get; set; }

            public Bird(string nam, string animalClass,
                string featherColor, double flightSpeed)
            {
                this.name = name;
                this.animalClass = animalClass;
                this.featherColor = featherColor;
                this.flightSpeed = flightSpeed;
            }
        }

        public class Fish : Animal
        {
            public string scaleColor { get; set; }
            public double swimmingSpeed { get; set; }

            public Fish(string name, string animalClass,
                string scaleColor, double swimmingSpeed)
            {
                this.name = name;
                this.animalClass = animalClass;
                this.scaleColor = scaleColor;
                this.swimmingSpeed = swimmingSpeed;
            }
        }

In this example, as all classes inherit from Animal class I could add them to an List<Animal>, but when I try to access the properties furColor and runningSpeed that are exclusive for Mammal class, I’ve got a error because them don’t belong to Animal class. To where these properties gone? How could I retrieve them?

Best regards,

Fabiano.

Answer 1

You can declare it as Mammal leopard = new Mammal(); to have access to it. Otherwise you'd need to cast leopard back to a mammal to retrieve them since Animal doesn't have the properties you require.

    Console.WriteLine("Name: {0}, Class: {1}, Fur Collor: {2}, Running Speed: {3} km/h.",
        leopard.name, leopard.animalClass, ((Mammal)leopard).furColor, ((Mammal)leopard).runningSpeed);