Intl.ListFormat.prototype.formatToParts()

The formatToParts() method of ListFormat instances returns an array of objects representing each part of the formatted string that would be returned by format(). It is useful for building custom strings from the locale-specific tokens.

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

const formatterEn = new Intl.ListFormat("en", {
  style: "long",
  type: "conjunction",
});

const formatterFr = new Intl.ListFormat("fr", {
  style: "long",
  type: "conjunction",
});

const partValuesEn = formatterEn.formatToParts(vehicles).map((p) => p.value);
const partValuesFr = formatterFr.formatToParts(vehicles).map((p) => p.value);

console.log(partValuesEn);
// Expected output: "["Motorcycle", ", ", "Bus", ", and ", "Car"]"
console.log(partValuesFr);
// Expected output: "["Motorcycle", ", ", "Bus", " et ", "Car"]"

Syntax

formatToParts(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

An Array of objects containing the formatted list in parts. Each object has two properties, type and value, each containing a string. The string concatenation of value, in the order provided, will result in the same string as format(). The type may be one of the following:

• literal
  • : Any string that’s a part of the format pattern; for example ", ", ", and", etc.
• element
  • : An element of the list, exactly as provided.

Examples

Using formatToParts()

const fruits = ["Apple", "Orange", "Pineapple"];
const myListFormat = new Intl.ListFormat("en-GB", {
  style: "long",
  type: "conjunction",
});

console.table(myListFormat.formatToParts(fruits));
// [
//  { "type": "element", "value": "Apple" },
//  { "type": "literal", "value": ", " },
//  { "type": "element", "value": "Orange" },
//  { "type": "literal", "value": " and " },
//  { "type": "element", "value": "Pineapple" }
// ]

Specifications

Browser compatibility

See also

• ListFormat
• Intl.ListFormat.prototype.format()