give the region

amit shukla

11y1.3kVisual Basic .NET

using System;
namespace Polymorphism
{
class A
{
public void Test() { Console.WriteLine("A::Test()"); }
}
class B : A
{
public new virtual void Test() { Console.WriteLine("B::Test()"); }
}
class C : B
{
public override void Test() { Console.WriteLine("C::Test()"); }
}
class Program
{
static void Main(string[] args)
{
A a = new A();
B b = new B();
C c = new C();
a.Test(); // output --> "A::Test()"
b.Test(); // output --> "B::Test()"
c.Test(); // output --> "C::Test()"
a = new B();
a.Test(); // output --> "A::Test()"
b = new C();
b.Test(); // output --> "C::Test()"
Console.ReadKey();
}
}
}

please give the logical answer.

why a.test() call A class function and why b.test() call C class test() function .

please share only technical region.

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Afzaal Ahmad Zeeshan11y ago
Quote:
In class C you are inheriting the class B. But in class C you are over riding the Bclass method so the out but here display is-
C::Test()

What does that have to do with the problem?
Upendra Pratap Shahi11y ago
In class C you are inheriting the class B. But in class C you are over riding the B class method so the out but here display is-
C::Test()
Syed Shanu11y ago
Its Clear from your program as
Class A has a Method Test.

In Class B you are inheriting class A and you have used the Virtual Method in Class B so at line no 10 in below statement it showing the Class A method.
A a = new A();
B b = new B();
C c = new C();
a.Test(); // output --> "A::Test()"
b.Test(); // output --> "B::Test()"
c.Test(); // output --> "C::Test()"
a = new B();
a.Test(); // output --> "A::Test()"

Same in C class you are inheriting the Class B.But in Class C you are over riding the B class method so the out but here display is "C::Test()"
b = new C();
b.Test(); // output --> "C::Test()"

Hope you understand now.
Check this link you will get more clear idea.
http://www.akadia.com/services/dotnet_polymorphism.html
Afzaal Ahmad Zeeshan11y ago
You are totally confusing yourself here Amit. You have not shown anywhere where the object a was having troubles. Now a also has troubles?

I would recommend that you please take some time and learn polymorphism. https://msdn.microsoft.com/en-us/library/ms173152.aspx?f=255&MSPPError=-2147217396
amit shukla11y ago
in this case ,
A a = new A();
B b=new B();
C c=new C();

b = new C();
but in this case b is the object reference of B class but in this time it is contain the reference address of C class.
so this is calling C class test functio.
But in this case
a = new B();
a.Test();

why a is calling A class test function and why a is not calling B Class function test function.
Afzaal Ahmad Zeeshan11y ago
Isn't that clear, in the code above
```
b = new C();
b.Test();
```
You are creating a new instance of C object in it. That is why it is calling the method of C class.