The Difference Between Array() and []
In JavaScript, Array() and [] are two ways to create arrays, but there is a subtle difference between them.
| Feature | Array() Constructor | Array Literal ([]) |
|---|---|---|
| Type of Creation | Built-in constructor function for creating arrays. | Shorthand notation for creating arrays. |
Call with new Keyword | Can be called with or without the new keyword. | Not applicable, as it is a shorthand notation, not a function. |
| Object Creation | When called with new, it creates a new array object. | Not applicable, as it doesn’t involve explicit object creation. |
| Return Type | Returns an array object. | Returns a newly created array. |
| Arguments | Can take arguments to specify initial elements of the array. | Can be used to create empty arrays or initialize with elements. |
| Example | javascript const array1 = new Array(1, 2, 3);// Using constructor with newconst array2 = Array(4, 5, 6); // Using constructor without new | javascript const array3 = [7, 8, 9]; // Creating an array using literal notation const emptyArray = []; // Creating an empty array |
When using Array() with the new keyword, it creates a new array object. When using [] (array literal notation), it also creates a new array object. However, if Array() is called without new and without arguments, it returns an empty array, while [] always creates a new empty array.
Example:
const newArray = Array(); // Returns an empty array
const literalArray = []; // Creates a new empty array
How to initialize an array in JavaScript ?
Initializing an array in JavaScript involves creating a variable and assigning it an array literal, which consists of square brackets enclosing optional comma-separated elements. These elements can be of any data type or can be omitted for an empty array.
To initialize an array in JavaScript we can use methods given below:
Table of Content
- Using an array as literal
- Using an array as an object/Array() constructor