Virtual Library Application in Python

Create a file named virtual_library.py and add the following code:

pythonCopy codeimport json
import os

class Book:
    def __init__(self, title, author, year, isbn):
        self.title = title
        self.author = author
        self.year = year
        self.isbn = isbn

    def to_dict(self):
        return {
            'title': self.title,
            'author': self.author,
            'year': self.year,
            'isbn': self.isbn,
        }

class VirtualLibrary:
    def __init__(self, filename='library.json'):
        self.filename = filename
        self.books = self.load_books()

    def load_books(self):
        """Load books from a JSON file."""
        if os.path.exists(self.filename):
            with open(self.filename, 'r') as file:
                return [Book(**data) for data in json.load(file)]
        return []

    def save_books(self):
        """Save books to a JSON file."""
        with open(self.filename, 'w') as file:
            json.dump([book.to_dict() for book in self.books], file)

    def add_book(self, title, author, year, isbn):
        """Add a new book to the library."""
        new_book = Book(title, author, year, isbn)
        self.books.append(new_book)
        self.save_books()
        print("Book added!")

    def view_books(self):
        """View all books in the library."""
        if not self.books:
            print("No books available.")
            return
        print("\nBooks in the Library:")
        for index, book in enumerate(self.books, start=1):
            print(f"{index}. {book.title} by {book.author} ({book.year}) - ISBN: {book.isbn}")
        print()

    def search_books(self, search_term):
        """Search for books by title or author."""
        results = [book for book in self.books if search_term.lower() in book.title.lower() or search_term.lower() in book.author.lower()]
        if results:
            print("\nSearch Results:")
            for index, book in enumerate(results, start=1):
                print(f"{index}. {book.title} by {book.author} ({book.year}) - ISBN: {book.isbn}")
        else:
            print("No books found matching that search term.")
        print()

    def run(self):
        """Run the virtual library application."""
        while True:
            print("Virtual Library")
            print("1. Add Book")
            print("2. View Books")
            print("3. Search Books")
            print("4. Exit")
            choice = input("Choose an option (1-4): ")

            if choice == '1':
                title = input("Enter the book title: ")
                author = input("Enter the author: ")
                year = input("Enter the publication year: ")
                isbn = input("Enter the ISBN: ")
                self.add_book(title, author, year, isbn)
            elif choice == '2':
                self.view_books()
            elif choice == '3':
                search_term = input("Enter title or author to search: ")
                self.search_books(search_term)
            elif choice == '4':
                print("Exiting the application.")
                break
            else:
                print("Invalid choice. Please try again.")

def main():
    library = VirtualLibrary()
    library.run()

if __name__ == "__main__":
    main()

Step 2: Running the Virtual Library Application

1. Open your terminal (or command prompt).
2. Navigate to the directory where you saved virtual_library.py.
3. Run the script using the command:bashCopy codepython virtual_library.py

How It Works

• Book Class: Represents a book with attributes like title, author, year, and ISBN.
• VirtualLibrary Class: Manages the collection of books, including loading from and saving to a JSON file.
• Functions:
  • load_books: Loads existing books from the JSON file.
  • save_books: Saves the current books back to the JSON file.
  • add_book: Adds a new book to the library.
  • view_books: Displays all stored books.
  • search_books: Searches for books by title or author.
• User Interface: A simple command-line interface that allows users to interact with the library.