Oops In C PlusPlus

Our aim: To help beginners
----- Waiting for content -----

What is the object in C++?

C++ Classes and Objects. 2.5. Class: The building block of C++ that leads to Object Oriented programming is a Class. It is a user defined data type, which holds its own data members and member functions, which can be accessed and used by creating an instance of that class.

Now Start Constructors.....
Coming soon.....

Member Functions in Classes:
There are 2 ways to define a member function:
1) Inside class definition
2)Outside class definition
To define a member function outside the class definition we have to use the scope resolution :: operator along with class name and function name.
// C++ program to demonstrate function
// declaration outside class

//
//using namespace std;
class Apss
{
public:
string apssname;
int id;

// printname is not defined inside class defination
void printname();

// printid is defined inside class defination
void printid()
{
cout

Accessing data members and member functions: The data members and member functions of class can be accessed using the dot(‘.’) operator with the object. For example if the name of object is obj and you want to access the member function with the name printName() then you will have to write obj.printName() .

Accessing Data Members:-

The public data members are also accessed in the same way given however the private data members are not allowed to be accessed directly by the object. Accessing a data member depends solely on the access control of that data member.
This access control is given by Access modifiers in C++. There are three access modifiers : public, private and protected.

// C++ program to demonstrate
// accessing of data members

//

//using namespace std;
class Apss
{
// Access specifier
public:

// Data Members
string appsname;

// Member Functions()
void printname()
{
cout

An Object is an instance of a Class. When a class is defined, no memory is allocated but when it is instantiated (i.e. an object is created) memory is allocated.

Defining Class and Declaring Objects

A class is defined in C++ using keyword class followed by the name of class. The body of class is defined inside the curly brackets and terminated by a semicolon at the end.

Declaring Objects: When a class is defined, only the specification for the object is defined; no memory or storage is allocated. To use the data and access functions defined in the class, you need to create objects.

Syntax:
ClassName ObjectName;

C++ Classes and Objects:-

Class: The building block of C++ that leads to Object Oriented programming is a Class. It is a user defined data type, which holds its own data members and member functions, which can be accessed and used by creating an instance of that class. A class is like a blueprint for an object.
For Example: Consider the Class of Cars. There may be many cars with different names and brand but all of them will share some common properties like all of them will have 4 wheels, Speed Limit, Mileage range etc. So here, Car is the class and wheels, speed limits, mileage are their properties.

A Class is a user defined data-type which have data members and member functions.
Data members are the data variables and member functions are the functions used to manipulate these variables and together these data members and member functions defines the properties and behavior of the objects in a Class.
In the above example of class Car, the data member will be speed limit, mileage etc and member functions can be apply brakes, increase speed etc.

An Object is an instance of a Class. When a class is defined, no memory is allocated but when it is instantiated (i.e. an object is created) memory is allocated.

Message Passing:-
----------------------
Objects communicate with one another by sending and receiving information to each other. A message for an object is a request for ex*****on of a procedure and therefore will invoke a function in the receiving object that generates the desired results. Message passing involves specifying the name of the object, the name of the function and the information to be sent.

Dynamic Binding:-
---------------------
In dynamic binding, the code to be executed in response to function call is decided at runtime. C++ has virtual functions to support this.

Polymorphism:-
------------------
polymorphism means ability to take more than one form. An operation may exhibit different behaviors in different instances. The behavior depends upon the types of data used in the operation.
C++ supports operator overloading and function overloading.
Operator overloading is the process of making an operator to exhibit different behaviors in different instances is known as operator overloading.
Function overloading is using a single function name to perform different types of tasks.
Polymorphism is extensively used in implementing inheritance.

Inheritance:
--------------
inheritance is the process by which objects of one class acquire the properties of objects of another class. It supports the concept of hierarchical classification. Inheritance provides re usability. This means that we can add additional features to an existing class without modifying it.

Encapsulation and Data abstraction:-

Wrapping up(combing) of data and functions into a single unit is known as encapsulation. The data is not accessible to the outside world and only those functions which are wrapping in the class can access it. This insulation of the data from direct access by the program is called data hiding or information hiding.

Data abstraction refers to, providing only needed information to the outside world and hiding implementation details. For example, consider a class Complex with public functions as getReal() and getImag(). We may implement the class as an array of size 2 or as two variables. The advantage of abstractions is, we can change implementation at any point, users of Complex class wont’t be affected as out method interface remains same. Had our implementation be public, we would not have been able to change it.

Class:-
-------
Class is a blueprint of data and functions or methods. Class does not take any space.

Syntax for class:

class class_name
{
private:
//data members and member functions declarations
public:
//data members and member functions declarations
protected:
//data members and member functions declarations
};

Class is a user defined data type like structures and unions in C.

By default class variables are private but in case of structure it is public. in above example person is a class.

Object:-
--------
Objects are basic run-time entities in an object oriented system, objects are instances of a class these are defined user defined data types.
ex:
class person
{
char name[20];
int id;
public:
void getdetails(){}
};

int main()
{
person p1; //p1 is a object
}
Object take up space in memory and have an associated address like a record in pascal or structure or union in C.

When a program is executed the objects interact by sending messages to one another.

Each object contains data and code to manipulate the data. Objects can interact without having to know details of each others data or code, it is sufficient to know the type of message accepted and type of response returned by the objects.

Basic Concepts of Object Oriented Programming using C++:-
Object oriented programming – As the name suggests uses objects in programming. Object oriented programming aims to implement real world entities like inheritance, hiding, polymorphism etc in programming. The main aim of OOP is to bind together the data and the functions that operates on them so that no other part of code can access this data except that function.

Polymorphism:-

Inheritance:-

Abstraction:-

Encapsulation:-

Learn Oops using c++