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regExp.toString

The toString() method returns a string representing the regular expression.

Syntax

regexObj.toString();

Return value

A string representing the given object.

Description

The RegExp object overrides the toString() method of the Object object; it does not inherit Object.prototype.toString(). For RegExp objects, the toString() method returns a string representation of the regular expression.

Examples

Using toString()

The following example displays the string value of a RegExp object:

var myExp = new RegExp('a+b+c');
console.log(myExp.toString());  // logs '/a+b+c/'

var foo = new RegExp('bar', 'g');
console.log(foo.toString());    // logs '/bar/g'

Empty regular expressions and escaping

Starting with ECMAScript 5, an empty regular expression returns the string "/(?:)/" and line terminators such as "\n" are escaped:

new RegExp().toString(); // "/(?:)/"

new RegExp('\n').toString() === '/\n/';  // true, prior to ES5
new RegExp('\n').toString() === '/\\n/'; // true, starting with ES5

Specifications

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes Yes Yes Yes Yes Yes
Escaping Yes Yes 38 Yes Yes Yes
Generic function ? ? 39 ? ? ?
Feature Android webview Chrome for Android Edge mobile Firefox for Android Opera Android iOS Safari Samsung Internet
Basic support Yes Yes Yes Yes Yes Yes ?
Escaping Yes Yes Yes 38 Yes Yes ?
Generic function ? ? ? 39 ? ? ?

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/toString