Instance methods in Javascript - Mini Project: Build & Apply

Instance Methods in JavaScript

📖 Scenario: You are creating a simple program to manage a library book. Each book has a title and an author. You want to add a method to the book that can show its details.

🎯 Goal: Build a JavaScript class called Book with an instance method getDetails that returns a string describing the book.

📋 What You'll Learn

Create a class named Book with a constructor that takes title and author as parameters

Add an instance method called getDetails inside the Book class

The getDetails method should return a string in the format: "Title: [title], Author: [author]"

Create an instance of Book with title "The Great Gatsby" and author "F. Scott Fitzgerald"

Call the getDetails method on the instance and print the result

💡 Why This Matters

🌍 Real World

Classes and instance methods are used to model real-world objects like books, users, or products in software.

💼 Career

Understanding instance methods is essential for building organized and reusable code in JavaScript applications.

1

Create the Book class with constructor

Create a class called Book with a constructor that takes title and author as parameters and assigns them to this.title and this.author.

Javascript

class Book {
  constructor(title, author) {
    // Your code here
  }
}

Need a hint?

Use this.title = title and this.author = author inside the constructor.

2

Add the instance method getDetails

Inside the Book class, add an instance method called getDetails that returns the string `Title: ${this.title}, Author: ${this.author}`.

Javascript

class Book {
  constructor(title, author) {
    this.title = title;
    this.author = author;
  }

  // Your code here
}

Need a hint?

Define getDetails() as a method returning the formatted string using template literals.

3

Create an instance of Book

Create a variable called myBook and assign it a new Book object with title "The Great Gatsby" and author "F. Scott Fitzgerald".

Javascript

class Book {
  constructor(title, author) {
    this.title = title;
    this.author = author;
  }

  getDetails() {
    return `Title: ${this.title}, Author: ${this.author}`;
  }
}

// Your code here

Need a hint?

Use new Book("The Great Gatsby", "F. Scott Fitzgerald") to create the instance.

4

Print the book details

Call the getDetails method on myBook and print the result using console.log.

Javascript

class Book {
  constructor(title, author) {
    this.title = title;
    this.author = author;
  }

  getDetails() {
    return `Title: ${this.title}, Author: ${this.author}`;
  }
}

const myBook = new Book("The Great Gatsby", "F. Scott Fitzgerald");

// Your code here

Need a hint?

Use console.log(myBook.getDetails()) to print the details.