The toString()
method returns a string representing the
regular expression.
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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
Specification |
---|
ECMAScript (ECMA-262) The definition of 'RegExp.prototype.toString' in that specification. |
Browser compatibility
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