JavaScript Array Methods

The basic structure of an HTML document consists of the following elements:

JavaScript provides a variety of built-in array methods that make it easy to work with arrays efficiently.

Here are some commonly used array methods:

push():

Adds one or more elements to the end of an array and returns the new length of the array.

let arr = [1, 2, 3];
arr.push(4);
// arr is now [1, 2, 3, 4]

Removes the last element from an array and returns that element.

let arr = [1, 2, 3];
let removedElement = arr.pop();
// arr is now [1, 2], removedElement is 3

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Removes the first element from an array and returns that element.

let arr = [1, 2, 3];
let shiftedElement = arr.shift();
// arr is now [2, 3], shiftedElement is 1

Adds one or more elements to the beginning of an array and returns the new length of the array.

let arr = [2, 3];
arr.unshift(1);
// arr is now [1, 2, 3]

Combines two or more arrays.

let arr1 = [1, 2];
let arr2 = [3, 4];
let combinedArr = arr1.concat(arr2);
// combinedArr is [1, 2, 3, 4]

Returns a shallow copy of a portion of an array into a new array object selected from start to end (end not included).

let arr = [1, 2, 3, 4, 5];
let newArr = arr.slice(1, 3);
// newArr is [2, 3]

Changes the contents of an array by removing or replacing existing elements and/or adding new elements in place.

let arr = [1, 2, 3, 4, 5];
arr.splice(2, 1, 'a', 'b');
// arr is now [1, 2, 'a', 'b', 4, 5]

Executes a provided function once for each array element.

let arr = [1, 2, 3];
arr.forEach(function(element) {
    console.log(element);
});

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Output: 1, 2, 3