using System;

using System.Collections.Generic;

​

​

public class Program

{

    public static void Main(string[] args)

    {

        List<Dog> dogs = new List<Dog>();

        dogs.Add(new Dog("Fido"));

        dogs.Add(new Dog("Bob"));

        dogs.Add(new Dog("Adam"));

                // ADD another dog named "Xander" to test the sorting

        dogs.Add(new Dog("Xander"));

        dogs.Sort();

        foreach(Dog dog in dogs)

            Console.WriteLine(dog.Describe());

        Console.ReadLine();

    }

}

​

interface IAnimal

{

    string Describe();

                // QUESTION Why does Describe() here does not have the {} brackets?

    /* The Describe() method in the IAnimal interface is written without braces {} because it is an auto-implemented property, 

    which means that the compiler automatically generates the implementation for the getter and setter methods. */

​

    string Name

    {

        get;

        set;

    }

}

​

class Dog : IAnimal, IComparable

                // QUESTION What is the IComparable interface?  Hint: you may want to look this up in the the official documentation

        /* The IComparable interface is used for objects that can be ordered or sorted. When a class implements the IComparable interface, 

        it means that instances of that class can be compared with other instances of the same class or with other objects that implement the IComparable interface. */

    {

        private string name;

​

        public Dog(string name)

        {

            this.Name = name;

        }

​

        public string Describe()

        {

            return "Hello, I'm a dog and my name is " + this.Name;

        }

​

                // QUESTION Can you describe what this method is doing?

            /* The Describe() method in the Dog class returns the string "Hello, I'm a dog and my name is " followed by the value of the Name property of the current Dog object. */

​

        public int CompareTo(object obj)

        {

            if(obj is IAnimal)

                return this.Name.CompareTo((obj as IAnimal).Name);

            return 0;

        }

​

        public string Name

        {

            get { return name; }

            set { name = value; }

        }

    }

​