The toLocaleString()
method returns a string representing the elements of the array. The elements are converted to Strings using their toLocaleString
methods and these Strings are separated by a locale-specific String (such as a comma “,”).
Syntax
arr.toLocaleString([locales[, options]]);
Parameters
locales
Optional- A string with a BCP 47 language tag, or an array of such strings. For the general form and interpretation of the
locales
argument, see theIntl
page. options
Optional- An object with configuration properties, for numbers see
Number.prototype.toLocaleString()
, and for dates seeDate.prototype.toLocaleString()
.
Return value
A string representing the elements of the array.
Polyfill
// https://tc39.github.io/ecma402/#sup-array.prototype.tolocalestring if (!Array.prototype.toLocaleString) { Object.defineProperty(Array.prototype, 'toLocaleString', { value: function(locales, options) { // 1. Let O be ? ToObject(this value). if (this == null) { throw new TypeError('"this" is null or not defined'); } var a = Object(this); // 2. Let len be ? ToLength(? Get(A, "length")). var len = a.length >>> 0; // 3. Let separator be the String value for the // list-separator String appropriate for the // host environment's current locale (this is // derived in an implementation-defined way). // NOTE: In this case, we will use a comma var separator = ','; // 4. If len is zero, return the empty String. if (len === 0) { return ''; } // 5. Let firstElement be ? Get(A, "0"). var firstElement = a[0]; // 6. If firstElement is undefined or null, then // a.Let R be the empty String. // 7. Else, // a. Let R be ? // ToString(? // Invoke( // firstElement, // "toLocaleString", // « locales, options » // ) // ) var r = firstElement == null ? '' : firstElement.toLocaleString(locales, options); // 8. Let k be 1. var k = 1; // 9. Repeat, while k < len while (k < len) { // a. Let S be a String value produced by // concatenating R and separator. var s = r + separator; // b. Let nextElement be ? Get(A, ToString(k)). var nextElement = a[k]; // c. If nextElement is undefined or null, then // i. Let R be the empty String. // d. Else, // i. Let R be ? // ToString(? // Invoke( // nextElement, // "toLocaleString", // « locales, options » // ) // ) r = nextElement == null ? '' : nextElement.toLocaleString(locales, options); // e. Let R be a String value produced by // concatenating S and R. r = s + r; // f. Increase k by 1. k++; } // 10. Return R. return r; } }); }
If you need to support truly obsolete JavaScript engines that don't support Object.defineProperty
, it's best not to polyfill Array.prototype
methods at all, as you can't make them non-enumerable.
Examples
Using locales
and options
The elements of the array are converted to strings using their toLocaleString
methods.
Object
:Object.prototype.toLocaleString()
Number
:Number.prototype.toLocaleString()
Date
:Date.prototype.toLocaleString()
Always display the currency for the strings and numbers in the prices
array:
var prices = ['¥7', 500, 8123, 12]; prices.toLocaleString('ja-JP', { style: 'currency', currency: 'JPY' }); // "¥7,¥500,¥8,123,¥12"
For more examples, see also the Intl
, NumberFormat
, and DateTimeFormat
pages.
Specifications
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
toLocaleString | Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 5.5 | Opera Full support 4 | Safari Full support 1 | WebView Android Full support ≤37 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 10.1 | Safari iOS Full support 1 | Samsung Internet Android Full support 1.0 | nodejs Full support 0.1.100 |
Optional locales parameter | Chrome Full support 24 | Edge Full support 79 | Firefox Full support 52 | IE No support No | Opera Full support 15 | Safari Full support 6.1 | WebView Android Full support ≤37 | Chrome Android Full support 25 | Firefox Android No support No | Opera Android Full support 14 | Safari iOS Full support 6.1 | Samsung Internet Android Full support 2.0 | nodejs
Full support
13.0.0
|
Optional options parameter | Chrome Full support 24 | Edge Full support 79 | Firefox Full support 52 | IE No support No | Opera Full support 15 | Safari Full support 6.1 | WebView Android Full support ≤37 | Chrome Android Full support 25 | Firefox Android No support No | Opera Android Full support 14 | Safari iOS Full support 6.1 | Samsung Internet Android Full support 2.0 | nodejs Full support 0.12 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.
- See implementation notes.