How to find Objects Containing Matching Elements from Arrays in Another Object ?

The task is to find objects that contain matching elements from arrays in another object. An object containing an array of values and a separate object. The objective is to determine whether the values present in the array are also present as keys in the separate object.

These are the following methods:

Using forEach loop

The forEach executes a provided function once for each array element. It does not return a new array. It is used to iterate through each ID in productIDs.ids and check if it exists in the productDetails object, pushing the corresponding product details into the matchingProducts array.

Example: Finding details of the products matching with IDs in the array using the forEach.

Javascript

// Object with product IDs
const productIDs = {
    ids: [101, 102, 104, 105]
};

// Separate object containing product details
const productDetails = {
    101: { name: "Laptop", price: 999 },
    102: { name: "Smartphone", price: 599 },
    103: { name: "Headphones", price: 99 },
    104: { name: "Tablet", price: 299 },
    106: { name: "Mouse", price: 29 }
};

// Function to find products by IDs using forEach
function findProductsByID(productIDs, productDetails) {
    const matchingProducts = [];
    productIDs.ids.forEach(id => {
        if (productDetails.hasOwnProperty(id)) {
            matchingProducts.push(productDetails[id]);
        }
    });
    return matchingProducts;
}

// Find products by IDs
const matchingProducts = findProductsByID(productIDs,
    productDetails);
console.log("Matching products:", matchingProducts);

Output

Matching products: [
  { name: 'Laptop', price: 999 },
  { name: 'Smartphone', price: 599 },
  { name: 'Tablet', price: 299 }
]

Using filter() and map() method

The filter() method creates a new array with all elements that pass the test implemented by the provided function. The findProductsByID function first uses filter to filter out the IDs that exist in the productDetails object. Then, the map() is used to map the filtered IDs to their corresponding product details.

Example: Finding details of the products matching with ids in the array using the filter and map method.

Javascript

// Object with product IDs
const productIDs = {
    ids: [101, 102, 104, 105]
};

// Separate object containing product details
const productDetails = {
    101: { name: "Laptop", price: 999 },
    102: { name: "Smartphone", price: 599 },
    103: { name: "Headphones", price: 99 },
    104: { name: "Tablet", price: 299 },
    106: { name: "Mouse", price: 29 }
};

// Function to find products by
// IDs using filter and map
function findProductsByID(productIDs,
    productDetails) {
    return productIDs.ids
        .filter(id => productDetails
            .hasOwnProperty(id))
        .map(id => productDetails[id]);
}

// Find products by IDs
const matchingProducts = findProductsByID(productIDs,
    productDetails);
console.log("Matching products:",
    matchingProducts);

Output

Matching products: [
  { name: 'Laptop', price: 999 },
  { name: 'Smartphone', price: 599 },
  { name: 'Tablet', price: 299 }
]

Using reduce() method

The reduce() method is used to accumulate the matching products. It iterates over each ID in the productIDs.ids array and checks if the ID exists in the productDetails object. If it does, it adds the corresponding product details to the accumulator (matchingProducts).

Example: Fnding details of the products matching with ids in the array using the reduce method.

Javascript

// Object with product IDs
const productIDs = {
    ids: [101, 102, 104, 105]
};

// Separate object containing product details
const productDetails = {
    101: { name: "Laptop", price: 999 },
    102: { name: "Smartphone", price: 599 },
    103: { name: "Headphones", price: 99 },
    104: { name: "Tablet", price: 299 },
    106: { name: "Mouse", price: 29 }
};

// Function to find products by IDs using reduce
function findProductsByID(productIDs,
    productDetails) {
    return productIDs.ids
        .reduce((matchingProducts, id) => {
            if (productDetails.hasOwnProperty(id)) {
                matchingProducts
                    .push(productDetails[id]);
            }
            return matchingProducts;
        }, []);
}

// Find products by IDs
const matchingProducts = findProductsByID(productIDs,
    productDetails);
console.log("Matching products:", matchingProducts);

Output

Matching products: [
  { name: 'Laptop', price: 999 },
  { name: 'Smartphone', price: 599 },
  { name: 'Tablet', price: 299 }
]