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Challenge: Implement Static Properties and Methods in a Class

Task

Imagine you're building an inventory management system for an online store. The Product class needs to keep track of the total number of products added to the inventory, as well as provide functionality to compare the prices of two products.

  1. Define a Static Property:
    • In the Product class, create a static property totalProducts initialized to 0;
    • Each time a new Product instance is created, increment totalProducts by 1 to keep track of how many products have been added to the inventory.
  2. Define a Static Method: Define a static method comparePrices(product1, product2) that takes two Product instances as parameters and returns:
    • "Product 1 is more expensive" if product1 has a higher price;
    • "Product 2 is more expensive" if product2 has a higher price;
    • "Both products have the same price" if they are equal.
class Product {
_____ _____ = 0; // Define static property for total products

constructor(name, price) {
this.name = name;
this.price = price;
Product._____+=1; // Increment totalProducts
}

// Static method to compare prices
_____ comparePrices(product1, product2) {
if (product1.price > product2.price) {
return _____;
} else if (_____ < _____) {
return _____;
} else {
return 'Both products have the same price';
}
}
}

// Testing
const product1 = new Product('Laptop', 1200);
const product2 = new Product('Smartphone', 800);
const product3 = new Product('Tablet', 1200);

console.log(Product.comparePrices(product1, product2)); // Expected: Product 1 is more expensive
console.log(Product.comparePrices(product1, product3)); // Expected: Both products have the same price
console.log(Product.comparePrices(product2, product3)); // Expected: Product 2 is more expensive

console.log(Product.totalProducts); // Expected: 3

              
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class Product {
  _____ _____ = 0; // Define static property for total products

  constructor(name, price) {
    this.name = name;
    this.price = price;
    Product._____+=1; // Increment totalProducts
  }

  // Static method to compare prices
  _____ comparePrices(product1, product2) {
    if (product1.price > product2.price) {
      return _____;
    } else if (_____ < _____) {
      return _____;
    } else {
      return 'Both products have the same price';
    }
  }
}

// Testing
const product1 = new Product('Laptop', 1200);
const product2 = new Product('Smartphone', 800);
const product3 = new Product('Tablet', 1200);

console.log(Product.comparePrices(product1, product2)); // Expected: Product 1 is more expensive
console.log(Product.comparePrices(product1, product3)); // Expected: Both products have the same price
console.log(Product.comparePrices(product2, product3)); // Expected: Product 2 is more expensive

console.log(Product.totalProducts); // Expected: 3
copy
  • Define a static property named totalProducts and initialize it to 0;
  • In the constructor, increment Product.totalProducts by 1 each time a new Product instance is created;
  • Define a static method comparePrices(product1, product2) that takes two parameters: product1 and product2;
  • In comparePrices, use an if statement to check if product1.price is greater than product2.price. If true, return "Product 1 is more expensive";
  • Use an else if statement to check if product1.price is less than product2.price. If true, return "Product 2 is more expensive".
class Product {
static totalProducts = 0; // Define static property for total products

constructor(name, price) {
this.name = name;
this.price = price;
Product.totalProducts+=1; // Increment totalProducts
}

// Static method to compare prices
static comparePrices(product1, product2) {
if (product1.price > product2.price) {
return 'Product 1 is more expensive';
} else if (product1.price < product2.price) {
return 'Product 2 is more expensive';
} else {
return 'Both products have the same price';
}
}
}

// Testing
const product1 = new Product('Laptop', 1200);
const product2 = new Product('Smartphone', 800);
const product3 = new Product('Tablet', 1200);

console.log(Product.comparePrices(product1, product2)); // Output: Product 1 is more expensive
console.log(Product.comparePrices(product1, product3)); // Output: Both products have the same price
console.log(Product.comparePrices(product2, product3)); // Output: Product 2 is more expensive

console.log(Product.totalProducts); // Output: 3

              
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class Product {
  static totalProducts = 0; // Define static property for total products

  constructor(name, price) {
    this.name = name;
    this.price = price;
    Product.totalProducts+=1; // Increment totalProducts
  }

  // Static method to compare prices
  static comparePrices(product1, product2) {
    if (product1.price > product2.price) {
      return 'Product 1 is more expensive';
    } else if (product1.price < product2.price) {
      return 'Product 2 is more expensive';
    } else {
      return 'Both products have the same price';
    }
  }
}

// Testing
const product1 = new Product('Laptop', 1200);
const product2 = new Product('Smartphone', 800);
const product3 = new Product('Tablet', 1200);

console.log(Product.comparePrices(product1, product2)); // Output: Product 1 is more expensive
console.log(Product.comparePrices(product1, product3)); // Output: Both products have the same price
console.log(Product.comparePrices(product2, product3)); // Output: Product 2 is more expensive

console.log(Product.totalProducts); // Output: 3
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Section 1. Chapter 13
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