JavaScript-Array-Methods

8 Must Know JavaScript Array Methods

JavaScript Array Methods

This repository provides examples and explanations of various JavaScript array methods. Each method is demonstrated with code snippets and comments for clarity.

Array of Objects Example

An array of objects, each containing a name and a price.

const items = [
    { name: "Bike", price: 100 },
    { name: "TV", price: 200 },
    { name: "Album", price: 10 },
    { name: "Book", price: 5 },
    { name: "Phone", price: 500 },
    { name: "Computer", price: 1000 },
    { name: "Keyboard", price: 25 },
];

Filter Method

The filter method creates a new array containing items with a price less than 100. The filter method does not change the original array.

const filteredItems = items.filter((item) => {
  return item.price < 100;
});
console.log(items); 
console.log(filteredItems);

Map Method

The map method transforms each element and creates a new array with the same length.

const itemNames = items.map((item) => {
  return item.name;
});
console.log(itemNames); // [ 'Bike', 'TV', 'Album', 'Book', 'Phone', 'Computer', 'Keyboard' ]

Find Method

The find method returns the first element in an array that satisfies a given condition. In this case, it searches for an object in the items array where the name property is equal to "Book" and returns that object. If no element satisfies the condition, find returns undefined.

const foundItem = items.find((item) => {
  return item.name === "Book";
});
console.log(foundItem); // { name: 'Book', price: 5 }

ForEach Method

The forEach method is used to iterate over an array and execute a function for each element. In this case, we are logging the name property of each item in the array to the console.

items.forEach((item) => {
  console.log(item.name);
});

Some Method

The some method returns a boolean value if any of the items in the array satisfy the condition.

const hasInexpensiveItems = items.some((item) => {
  return item.price < 100;
});
console.log(hasInexpensiveItems); // true

Every Method

The every method returns a boolean value if all of the items in the array satisfy the condition.

const expensiveItems = items.every((item) => {
  return item.price > 100;
});
console.log(expensiveItems); // false

Reduce Method

The reduce method is used to calculate the total price of all items in the 'items' array.

const total = items.reduce((currentTotal, item) => {
  return item.price + currentTotal;
}, 0);
console.log(total); // 1840

Includes Method

The includes method returns a boolean value if the array contains the specified value.

const includeValue = numbers.includes(2);
console.log(includeValue); // true