What is the real significance(use) of polymorphism

Question

I am new to OOP. Though I understand what polymorphism is, but I can\'t get the real use of it. I can have functions with different name. Why should I try to implement polym

Answer 1

Advantage of polymorphism is client code doesn't need to care about the actual implementation of a method. Take look at the following example. Here CarBuilder doesn't know anything about ProduceCar().Once it is given a list of cars (CarsToProduceList) it will produce all the necessary cars accordingly.

class CarBase
{
    public virtual void ProduceCar()
    {
        Console.WriteLine("don't know how to produce");
    }
}

class CarToyota : CarBase
{
    public override void ProduceCar()
    {
        Console.WriteLine("Producing Toyota Car ");
    }
}

class CarBmw : CarBase
{
    public override void ProduceCar()
    {
        Console.WriteLine("Producing Bmw Car");
    }
}

class CarUnknown : CarBase { }

class CarBuilder
{
    public List CarsToProduceList { get; set; }

    public void ProduceCars()
    {
        if (null != CarsToProduceList)
        {
            foreach (CarBase car in CarsToProduceList)
            {
                car.ProduceCar();// doesn't know how to produce
            }
        }

    }
}

class Program
{
    static void Main(string[] args)
    {
        CarBuilder carbuilder = new CarBuilder();
        carbuilder.CarsToProduceList = new List() { new CarBmw(), new CarToyota(), new CarUnknown() };            
        carbuilder.ProduceCars();
    }
}