This document discusses polymorphism in C# through method overloading and overriding. It shows how to create a base DrawingObject class that can be inherited by Line, Circle, and Square classes, where each subclass overrides the Draw method to output its type. The Main method creates instances of each subclass and calls their Draw methods to demonstrate polymorphism. The document also compares abstract classes and interfaces, noting that abstract classes can contain implemented methods while interfaces only contain signatures, and interfaces allow multiple inheritance while abstract classes do not.

1. We Can Implement Polymorphism In C #
Through Method Overloading and Method
Overriding
POLYMORPHISM
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2. Method Overloading & Method Overriding
 Public class Drawing Object
 {
 public void Draw()
 {
 Console .Write Line(“ I’m just
a generic drawing object.”);
 }
 }
POLYMORPHISM
Shows the drawing object class this
will be the base class for other
objects to inherit from ,It has a
single method named Draw() .the
Draw Method has a virtual Modifier
.This virtual Modifier indicates to
derived classes that they can
override this method
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3.  Public class Line: Drawing Object
 {
 public override void Draw()
 {
 Console .Write Line(“ I’m a Line.”);
 }
 }
 Public class Circle : Drawing Object
 {
 public override void Draw()
 {
 Console .Write Line (“ I’m a Circle .”);
METHODOVERLOADING&
METHODOVERRIDING
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4. Public class Square :
Drawing Object
{
 public override void Draw()
{
Console .Write Line(“ I’m a
Square.”);
}
}
Method
Overloading
& Method
Overriding
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5.  Class Main
 {
 Public static void main()
 {
 Drawing ObjdObj=newDrawingObj();
 dObj.Draw();
 DrawingObject li=new Line();
 Li.Draw();
 DrawingObject cr=new Circle();
 Cr.Draw();
 DrawingObject sq=newSquare();
 Sq.Draw();
 Console.ReadKey();
 }
 }
 }
Method
Overloading
& Method
Overriding
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6. An abstract class can
implement methods
An abstract class can
contain fields
An abstract class can
contain constructors
or destructors
An interface cannot
implement methods
An interface can
inherit from another
class
An interface can
contain signature
ABSTRACT CLASS & INTERFACE
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7. An abstract class
cannot be inherited
from by a class .
Abstract class cannot
support multiple
inheritances
Interface cannot
contain constructors
or destructors
Interface can
support multiple
inheritances
ABSTRACT CLASS & INTERFACE
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8. An interface look like a class but has no
implementation.The only things that they
contain are only signature of methods events
and or properties .the reason interface only
provide declarations is because they are
inherit by classes and which provide
implementation for each interface member
declared
INTERFACE
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9. An Abstract class has no implementation like
interface . Implementation of methods can be
use by the child class
ABSTRACT CLASS
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