Array.prototype.join()

Summary

The join() method joins all elements of an array into a string.

Syntax

str = arr.join([separator = ','])

Parameters

separator

Optional. Specifies a string to separate each element of the array. The separator is converted to a string if necessary. If omitted, the array elements are separated with a comma. If separator is an empty string all ellements are joined without any characters in between them.

Description

The string conversions of all array elements are joined into one string.

Examples

Example: Joining an array four different ways

The following example creates an array, a, with three elements, then joins the array four times: using the default separator, then a comma and a space, then a plus and an empty string.

var a = ['Wind', 'Rain', 'Fire'];
var myVar1 = a.join();      // assigns 'Wind,Rain,Fire' to myVar1
var myVar2 = a.join(', ');  // assigns 'Wind, Rain, Fire' to myVar2
var myVar3 = a.join(' + '); // assigns 'Wind + Rain + Fire' to myVar3
var myVar4 = a.join('');    // assigns 'WindRainFire' to myVar4

Specifications

Browser compatibility

See also

• String.prototype.split()
• Array.prototype.toString()
• TypedArray.prototype.join()