Array in Javascript: Arrays are simple and efficient data structures in Javascript that allow to store more than one value in a single variable. Unlike other arrays, arrays in Javascript have no restrictions based on the data type. It does not need to have similar element constraints and, hence, is easier and more effective to use. Let us get more insights about arrays in Javascript from this article.
What is an Array in Javascript?
Arrays in Javascript are a data structure used to store multiple values inside a single variable. The values in Javascript arrays can be of any data type, such as string, integer, double, float, char, another array, etc.Â
This data structure is used in various programming operations and also helps in building data structures and algorithms. However, an Array in JavaScript is more efficient than other arrays. Let us know how under this article.
Also Read: Array Java: Declare, Define, and Access Array
Array in Javascript: How to Declare Array
We can easily declare arrays in Javascript using square brackets. There are two primary ways to declare an array in Javascript.
1. Using Common Literal Syntax
 In JavaScript, array elements are stored within a square bracket. One array variable can consist of different data types such as string, integer, double, char, etc.
| Array in Javascript: Using Syntax |
| let fruits = [‘apple’, ‘banana’, ‘mango’];
let num = [1, 2, 3, 4, 5]; let mixedArray = [1, ‘two’, true, { key: ‘value’ }]; |
2. Using the Array Constructor
The Array constructor is used to declare an array in the table below.
| Array in Javascript: Array Syntax |
| let emptyArray = new Array();
let num = new Array(1, 2, 3, 4, 5); |
The elements in these arrays can be accessed using their index numbers.Â
Array in Javascript: How to Change an Element in an Array?
Using the assignment operators, we can change elements in an array at any index.Â
| Array in Javascript: Changing Element in Array |
| let myArray = [10, 20, 30];
// To change the element at index 1, use the index. myArray[1] = 25; console.log(myArray);Â // Outputs: [10, 25, 30] |
Array in Javascript: Accessing Array Elements
The elements in the javascript arrays can be accessed using the index number. The indexing in the Javascript array starts with the zero index. We can use these index numbers to access elements in an array.
| Array in Javascript: Accessing Elements of Array |
| let myArray = [10, 20, 30, 40, 50];
let index = 2; let element = myArray[index];Â // Gets the element at the specified index which is 2 console.log(element);Â // Outputs: 30 |
Array in Javascript: Advantages of using Array
Javascript arrays are used for various applications in programming and are more efficient than other arrays. Some of the advantages of using the javascript array are as follows.
- Arrays in Javascript help to make an ordered collection of elements. They can be easily accessed and iterated.
- Javascript arrays are specialized objects consisting of different operations and methods.
- Elements in arrays can be accessed using their index number.
- Array in Javascript are of dynamic size, which helps to manipulate elements easily.
- Javascript in arrays can hold different data types within the same array.Â
- The javascript arrays have built-in methods such as pop, map, filter, reduce, etc.
- Arrays in Javascript allocate memory in contiguous memory locations.
Also Read: Array Of Objects In Java: How to Create Array of Objects in Java?
Array in Javascript: MethodsÂ
Some of the predefined methods in JavaScript arrays are mentioned below.
| Array in Javascript: Methods | |
| Method | Description |
| indexOf() | It helps to search for the specified element present in the given array. It returns the index of the first match found in the array. |
| isArray() | It tells whether a value passed in the method is an array. |
| map() | It calls a function for every element in the array to create a new array. |
| pop() | It returns an array after removing its top element. |
| push() | It pushes elements to the end of a javascript array. |
| slice() | It returns a part of the array from the original array. |
| sort() | It sorts the elements in an array in ascending or descending order. |
| splice() | It adds or removes an element from the array. |
| concat() | It adds an array object to the end of the array and returns two or more merged arrays. |
| every() | It checks whether elements in the array satisfy the given conditions. |
| fill() | It fills static values within an array. |
| filter() | It provides preconditions to return a new array consisting of elements that satisfy the condition. |
| find() | It finds the first index of a value in an array. |
| findIndex() | It returns the index of the elements satisfying a given condition. |
| forEach() | It checks a given condition on each element of an array. |
| joins() | It adds together elements of an array to a string. |
| lastIndexOf() | It returns the last index of an element or last match. |
| toString() | It converts an array element to a string. |
| delete() | It returns an undefined hole in an array. |
| length() | It returns the length of the array in Javascript. |
| copyWithin() | It copies array elements directly to another index of an array. It overwrites the existing values and does not add items to the array. |
Array in Javascript: Browser Support
Javascript arrays are supported on various devices and browsers. Check out some of the latest browsers that support arrays in JavaScript.
- Google ChromeÂ
- Microsoft EdgeÂ
- Firefox
- SafariÂ
- Opera Mini
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Array in Javascript FAQs
What are arrays in Javascript?
Arrays in Javascript are a data structure used to store multiple values inside a single variable. The values in Javascript arrays can be of any data type, such as string, integer, double, float, char, another array, etc.
Are arrays Javascript objects?
Arrays in Javascript are special types of objects, which makes them more effective than other arrays. It returns an object value.
Is an array a class or an object in Javascript?
Arrays in JavaScript are objects that consist of different operations and methods.
