Symbol.search

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.

The Symbol.search static data property represents the well-known symbol Symbol.search. The String.prototype.search() method looks up this symbol on its first argument for the method that returns the index within a string that matches the current object.

For more information, see RegExp.prototype[Symbol.search]() and String.prototype.search().

Try it

class Search1 {
  constructor(value) {
    this.value = value;
  }
  [Symbol.search](string) {
    return string.indexOf(this.value);
  }
}

console.log("foobar".search(new Search1("bar")));
// Expected output: 3

Value

The well-known symbol Symbol.search.

Property attributes of Symbol.search

Writable	no
Enumerable	no
Configurable	no

Examples

Custom string search

js
class CaseInsensitiveSearch {
  constructor(value) {
    this.value = value.toLowerCase();
  }
  [Symbol.search](string) {
    return string.toLowerCase().indexOf(this.value);
  }
}

console.log("foobar".search(new CaseInsensitiveSearch("BaR"))); // 3