Learn Why class and object Is Important & What Is Object In C++?

class is a user-defined data type. class is defined by class keyword. Class And Object are the most important  And common concepts in object-oriented programming languages. class is widely used in C++. you can declare multiple classes in one C++ program

class and object in c++

What is Class?

Class is a box. class does hold member methods functions and data members (variables) in the class body. The class uses a data-hiding concept. the class has no limit for creating a function and variable. member functions and data member declared by curly braces

basic structures of class

CLASS class_name
{
 
 // declare  variable
 
 // access specifier
 
 // function code
 
};

the class has 3 access specifiers.

  1. Public
  2. Private
  3. Protected

What is an Object?

when you define a class then not used memory but when you create class objects then memory will be allocated.

Also Read This :- inline function in c++

you can not operate class without objects. when you created multiple objects then memory will separate allocated. if you want to call a method of a class, first you write the object name after write dot(.) and write the method name.

Example of class and object

#include <iostream>
using namespace std;

class item
{
    int item_no; // Private Member
    float cost;  // Private Member

public:
    void getdata(int a, int b)
    {
        item_no = a;
        cost = b;
    }

    void putdata()
    {
        cout << "Item_no = " << item_no << endl;
        cout << "Cost = " << cost << endl;
    }
};

int main()
{
    item i1, i2;

    i1.getdata(101, 5000);
    i2.getdata(102, 2000);

    cout << " I1 Object : " << endl;
    i1.putdata();

    cout << " I2 Object : " << endl;
    i2.putdata();
    return 0;
}

output

I1 Object : 
Item_no = 101
Cost = 5000
 I2 Object : 
Item_no = 102
Cost = 2000