In c# Parent class object initialized by child class instance

Question

I have seen many examples on the concepts of inheritance, abstraction and polymorphism where an object of a base class is being initialized by a child class like below:

BaseClass obj1 = new ChildClass();

Most of the examples only used unreal and simple examples, but I always wanted to know the real life examples on what scenarios these can be used.

There are thousands, if not millions, of such examples. Can you be a bit more specific about what is confusing you? By the way, thats not "initializing a base class object", you are just assigning a derived class instance to a base class reference (upcasting). — BradleyDotNET, Jan 26 '15 at 23:18
Please don't ask such broad questions which are even not a real programming issue. See here: http://stackoverflow.com/help/how-to-ask — Quality Catalyst, Jan 26 '15 at 23:37
I should have put this initially, why do I have to use Parent class object and assign it an instance of child class. — rocket.net, Jan 27 '15 at 00:06

score 0 · Answer 1 · answered Jan 26 '15 at 23:18

0

Take Vehicle and Car as an example, where Vehicle is the superclass and Car is the subclass

Then you can write the code as

Vehicle vehicle = new Car();

answered Jan 26 '15 at 23:18

Low Flying Pelican

5,974
1
32
43

1

Besides being an answer to a terrible question, I'm not sure this qualifies as "real life" (unless you are writing an auto-related program). – BradleyDotNET Jan 26 '15 at 23:21
vehicle and car are used in everyday life, as far as I understand all he needs to is understand how to apply the concept. – Low Flying Pelican Jan 26 '15 at 23:28
Different interpretation then, I thought it was "where you use it in real-life programming". – BradleyDotNET Jan 26 '15 at 23:29
Well, if you read what I have wrote (where Vehicle is the superclass and Car is the subclass), Car inherits from Vehicle not other way round. – Low Flying Pelican Jan 26 '15 at 23:37
For what its worth, you and the OP do have the inheritance relation correct from what I can see. – BradleyDotNET Jan 26 '15 at 23:39
Sorry mate, actually I was referring the user "query analyst", as he was mentioning inheritance relation was wrong. – Low Flying Pelican Jan 26 '15 at 23:46

score 0 · Answer 2 · answered Jul 20 '15 at 10:11

class Program
{
    static void Main(string[] args)
    {
        var product = new Product();
        var status = product.Process();
    }
}

public class Product : Provider
{
    string provId = "ABC101";

    public bool Process()
    {
        var prodProv = new Provider(provId);
        this.QueryProvider();
        return true;
    }
}

public class Provider
{
    private string _providerId;

    public Provider(string provId)
    {
        _providerId = provId;
    }

    public void QueryProvider()
    {
        // Execute Provider logic here
    }
}

In c# Parent class object initialized by child class instance

2 Answers2