OOPS Concepts with Brief explanation and example.asp.net and java
Object Oriented
Programming
|
Object is an real world entity such as a chair, pen
|
etc..,
|
Object Oriented Programming is a methodology to
|
design a
program using class and objects.
|
OOP has
some concepts to develop a program
|
Object
|
Class
|
Inheritance
|
Polymorphism
|
Abstraction
|
Encapsulation
|
Object:
|
Object is a thing, object performs set of properties
|
and activities
it defines the object behavior.
|
For example car is a object it performs some activity
|
like drive
one place to another.
|
Object is known as instance of object.
|
BMW Car object=new
BMW Car();
|
Class:
|
Class is representation of what is an object. (Or)
|
class is a blue print or template that has details
about object.
Class is a set methods and properties.
Public class
Car
{
}
|
Example for Class and object:
|
Consider
car as example
|
Car is a
class it has properties like
|
Design
|
Number of wheels
|
Here BMW
is an object. It’s comes under car class because it
has all
car properties.
|
BMW object=new BMW();
|
Public class car
|
{
|
Void design();
|
Void number of wheels();
|
}
|
Inheritance:
|
When a class includes a property of another class is known as
|
inheritance.
Here inheriting means receiving or deriving.
One class is having another class of property. Because it receiving
(or) deriving properties from another class
it is said to be
inheritance.
Class class1
{
//content
}
Class class2:class1
{
//content
}
|
Real time example for inheritance:
|
Consider family as example.
|
In family the child get properties form father or mother.
|
Here child inheriting behavior from father.
|
Class father
{
Behavior;
}
Class child
: Father
{
Father object=new
Father.behavior();
}
|
Polymorphism:
|
Here polymorphism means many forms. Or one function
|
behaves
different forms.
Polymorphism achieve by overloading and overriding.
Also known
as compile time polymorphism and run time
polymorphism.
|
Overloading:
|
It is an
ability to define same name for several methods.
|
Example for method overloading: |
Class sum
{
int add(int
a, int b)
{
Return
a+b;
}
int add(int
a, int b, int c)
{
Return
a+b+c;
}
int add(int
a, int b, int c, int d)
{
Return
a+b+c+d;
}
}
Public static
void Main()
{
Sum obj =new sum();
Console.writeline(“some
of a+b”+obj.sum(10,20));
Console.writeline(“some
of a+b+c”+obj.sum(10,20,30));
Console.writeline(“some
of a+b+c+d”+obj.sum(10,20,30,40));
}
Output:
Sum of a+b=30
Sum of a+b+c=60
Sum of a+b+C+d=120
|
Overriding:
|
Method override
occurs when child class declare a method with same arguments already in
parent class.
|
class CarClass
{
public virtual int speedLimit()
{
return 100;
}
}
class Ford : CarClass
{
public override int speedLimit()
{
return 150;
}
public static void Main()
{
Ford obj = new Ford();
int num= obj.speedLimit();
Console.WriteLine("Speed
Limit is: "+num);
Console.ReadKey();
}
}
|
Encapsulation:
|
Warping up data and methods in to a single unit is
|
known as encapsulation.
Real time
example:
Consider mobile as example.
The circuit board and all the connections combined
into a single unit.
We don’t know the internal process. We just know
how to make call, and taking pictures etc..,
|
public class School
{
private string Schooldepartname;
public string SchoolDepartname
{
get
{
return Schooldepartname;
}
set
{
Schooldepartname = value;
}
}
}
public class Departmentmain
{
public static int Main(string[]
args)
{
School d = new School();
d.SchoolDepartname = "Communication";
Console.WriteLine("The Dept. Name
is :{0}", d.SchoolDepartname);
Console.ReadKey();
return 0;
|
}
|
}
|
Abstraction:
|
Abstraction
shows the necessary data and hides the un
necessary
data.
Example:
A Laptop
consists of many things such as processor,
motherboard,
RAM, keyboard, LCD screen etc. To use it, you
don't need
to know how internally LCD screens, keyboard, web
camera works.
You just need to know how to operate the
laptop by
switching it on.
|
public abstract
class university
{
public abstract void BTech();
public abstract void MBA();
}
|
public class GBTU : university
{
public override void BTech()
{
Console.WriteLine("GBTU BTech Fee
50000/-");
}
public override void MBA()
{
Console.WriteLine("GBTU MBA Fee 100000/-");
}
}
public class MTU : university
{
public override void BTech()
{
Console.WriteLine("MTU BTech Fee 40000/-");
}
public override void MBA()
{
Console.WriteLine("MTU MBA Fee 800000/-");
}
}
|
class Program
{
|
static void
Main(string[] args)
{
GBTU g = new GBTU();
g.BTech();
g.MBA();
MTU m = new MTU();
m.BTech();
m.MBA();
Console.ReadLine();
}
}
}
|
Output-
GBTU BTech
Fee 50000/-
GBTU MBA
Fee 100000/-
MTU BTech
Fee 40000/-
|
Post a Comment