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CSSStyleDeclaration JS Conversion


JavaScript Array concat()

Examples

Join two arrays:

const arr1 = ["Cecilie", "Lone"];
const arr2 = ["Emil", "Tobias", "Linus"];
const children = arr1.concat(arr2);

Try it Yourself »

Join three arrays:

const arr1 = ["Cecilie", "Lone"];
const arr2 = ["Emil", "Tobias", "Linus"];
const arr3 = ["Robin"];
const children = arr1.concat(arr2, arr3);
Try it Yourself »

More examples below.


Description

The concat() method concatenates (joins) two or more arrays.

The concat() method returns a new array, containing the joined arrays.

The concat() method does not change the existing arrays.


Syntax

array1.concat(array2, array3, ..., arrayX)

Parameters

Parameter Description
array1,... Required.
The array(s) to be concatenated.

Return Value

Type Description
ArrayThe content from the joined arrays.


More Examples

Concatenate strings and numbers:

const arr1 = ["Cecilie", "Lone"];
const arr2 = [1, 2, 3];
const arr3 = arr1.concat(arr2);

Try it Yourself »

Concatenate nested arrays:

const arr1 = [1, 2, [3, 4]];
const arr2 = [[5, 6], 7, 8];
const arr3 = arr1.concat(arr2);
Try it Yourself »

Browser Support

concat() is an ECMAScript1 (ES1) feature.

ES1 (JavaScript 1997) is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes Yes


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