The compare() method of Intl.Collator instances compares two strings according to the sort order of this collator object.

Syntax

compare(string1, string2)

Parameters

• string1, string2
  • : The strings to compare against each other.

Return value

A number indicating how string1 and string2 compare to each other according to the sort order of this Intl.Collator object:

• A negative value if string1 comes before string2;
• A positive value if string1 comes after string2;
• 0 if they are considered equal.

Examples

Using compare for array sort

Use the compare function for sorting arrays. Note that the function is bound to the collator from which it was obtained, so it can be passed directly to Array.prototype.sort.

const a = ["Offenbach", "Österreich", "Odenwald"];
const collator = new Intl.Collator("de-u-co-phonebk");
a.sort(collator.compare);
console.log(a.join(", ")); // "Odenwald, Österreich, Offenbach"

Using compare for array search

Use the compare function for finding matching strings in arrays:

const a = ["Congrès", "congres", "Assemblée", "poisson"];
const collator = new Intl.Collator("fr", {
  usage: "search",
  sensitivity: "base",
});
const s = "congres";
const matches = a.filter((v) => collator.compare(v, s) === 0);
console.log(matches.join(", ")); // "Congrès, congres"

Specifications

Browser compatibility

See also

• Intl.Collator
• String.prototype.localeCompare