Why object-oriented programming is used in C++ - See It in Action

Why Object-Oriented Programming is Used

📖 Scenario: Imagine you are building a simple program to manage a library. You want to keep track of books and their details like title, author, and whether they are checked out. Using object-oriented programming helps organize this information clearly and makes your program easier to manage and expand.

🎯 Goal: You will create a simple class to represent a book, set up some book objects, and then display their details. This will show why object-oriented programming is useful for organizing related data and actions together.

📋 What You'll Learn

Create a class called Book with three public member variables: title, author, and isCheckedOut.

Create two Book objects with specific titles and authors, and set their isCheckedOut status.

Write a function to display the details of a Book object.

Call the display function for each book to show their information.

💡 Why This Matters

🌍 Real World

Object-oriented programming is used to model real-world things like books, cars, or people in software. It helps organize data and actions together, making programs easier to understand and change.

💼 Career

Many software jobs require understanding classes and objects because they are the foundation of large applications, from games to business software.

1

Create the Book class

Create a class called Book with three public member variables: title (string), author (string), and isCheckedOut (bool).

C++

#include 
#include 

using namespace std;

// Create class Book with public members title, author, isCheckedOut
// Your code here

Need a hint?

Use the class keyword to define Book. Declare the variables as public inside the class.

2

Create two Book objects

Create two Book objects named book1 and book2. Set book1.title to "The Great Gatsby", book1.author to "F. Scott Fitzgerald", and book1.isCheckedOut to false. Set book2.title to "1984", book2.author to "George Orwell", and book2.isCheckedOut to true.

C++

#include 
#include 

using namespace std;

class Book {
public:
    string title;
    string author;
    bool isCheckedOut;
};

// Create book1 and book2 with given details
// Your code here

Need a hint?

Create objects using the class name and set each member variable using dot notation.

3

Write a function to display book details

Write a function called displayBook that takes a Book object as a parameter and prints its title, author, and isCheckedOut status as "Available" if isCheckedOut is false, or "Checked out" if true.

C++

#include 
#include 

using namespace std;

class Book {
public:
    string title;
    string author;
    bool isCheckedOut;
};

// Write displayBook function here

int main() {
    Book book1;
    book1.title = "The Great Gatsby";
    book1.author = "F. Scott Fitzgerald";
    book1.isCheckedOut = false;

    Book book2;
    book2.title = "1984";
    book2.author = "George Orwell";
    book2.isCheckedOut = true;

    // Your code here
}

Need a hint?

Use a function that takes a const Book& parameter to avoid copying. Use cout to print each detail. Use the conditional operator to print status.

4

Display details of both books

Call the displayBook function for book1 and book2 inside main() to print their details.

C++

#include 
#include 

using namespace std;

class Book {
public:
    string title;
    string author;
    bool isCheckedOut;
};

void displayBook(const Book& book) {
    cout << "Title: " << book.title << endl;
    cout << "Author: " << book.author << endl;
    cout << "Status: " << (book.isCheckedOut ? "Checked out" : "Available") << endl;
}

int main() {
    Book book1;
    book1.title = "The Great Gatsby";
    book1.author = "F. Scott Fitzgerald";
    book1.isCheckedOut = false;

    Book book2;
    book2.title = "1984";
    book2.author = "George Orwell";
    book2.isCheckedOut = true;

    // Call displayBook for book1 and book2
    // Your code here
}

Need a hint?

Call displayBook(book1); and displayBook(book2); inside main(). Add a blank line between outputs for readability.