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.