ThetoString() method ofRegExp instances returns a string representing this regular expression.

Try it

console.log(new RegExp("a+b+c"));// Expected output: /a+b+c/console.log(new RegExp("a+b+c").toString());// Expected output: "/a+b+c/"console.log(new RegExp("bar", "g").toString());// Expected output: "/bar/g"console.log(new RegExp("\n", "g").toString());// Expected output: "/\n/g"console.log(new RegExp("\\n", "g").toString());// Expected output: "/\n/g"

Syntax

toString()

Parameters

None.

Return value

A string representing the given object.

Description

TheRegExp object overrides thetoString() method of theObject object; it does not inheritObject.prototype.toString(). ForRegExp objects, thetoString() method returns a string representation of the regular expression.

In practice, it reads the regex'ssource andflags properties and returns a string in the form/source/flags. ThetoString() return value is guaranteed to be a parsable regex literal, although it may not be the exact same text as what was originally specified for the regex (for example, the flags may be reordered).

Examples

Using toString()

The following example displays the string value of aRegExp object:

const myExp = new RegExp("a+b+c");console.log(myExp.toString()); // '/a+b+c/'const foo = new RegExp("bar", "g");console.log(foo.toString()); // '/bar/g'

Empty regular expressions and escaping

SincetoString() accesses thesource property, an empty regular expression returns the string"/(?:)/", and line terminators such as\n are escaped. This makes the returned value always a valid regex literal.

new RegExp().toString(); // "/(?:)/"new RegExp("\n").toString() === "/\\n/"; // true

Specifications

Browser compatibility

See also

• Object.prototype.toString()