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javascript instance method

Intl.ListFormat.prototype.format()

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The format() method of ListFormat instances returns a string with a language-specific representation of the list.

Interactive exampleOpen the canonical MDN source to run this embedded demo.
const vehicles = ["Motorcycle", "Bus", "Car"];

const formatter = new Intl.ListFormat("en", {
  style: "long",
  type: "conjunction",
});
console.log(formatter.format(vehicles));
// Expected output: "Motorcycle, Bus, and Car"

const formatter2 = new Intl.ListFormat("de", {
  style: "short",
  type: "disjunction",
});
console.log(formatter2.format(vehicles));
// Expected output: "Motorcycle, Bus oder Car"

const formatter3 = new Intl.ListFormat("en", { style: "narrow", type: "unit" });
console.log(formatter3.format(vehicles));
// Expected output: "Motorcycle Bus Car"

Syntax

format(list)

Parameters

  • list
    • : An iterable object, such as an Array, containing strings. Omitting it results in formatting the empty array, which could be slightly confusing, so it is advisable to always explicitly pass a list.

Return value

A language-specific formatted string representing the elements of the list.

[!NOTE] Most of the time, the formatting returned by format() is consistent. However, the output may vary between implementations, even within the same locale — output variations are by design and allowed by the specification. It may also not be what you expect. For example, the string may use non-breaking spaces or be surrounded by bidirectional control characters. You should not compare the results of format() to hardcoded constants.

Examples

Using format

The following example shows how to create a List formatter using the English language.

const list = ["Motorcycle", "Bus", "Car"];

console.log(
  new Intl.ListFormat("en-GB", { style: "long", type: "conjunction" }).format(
    list,
  ),
);
// Motorcycle, Bus and Car

console.log(
  new Intl.ListFormat("en-GB", { style: "short", type: "disjunction" }).format(
    list,
  ),
);
// Motorcycle, Bus or Car

console.log(
  new Intl.ListFormat("en-GB", { style: "narrow", type: "unit" }).format(list),
);
// Motorcycle Bus Car

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also