String.prototype.valueOf()
The valueOf()
method returns the primitive value of a String
object.
Syntax
JavaScript
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<var>str</var>.valueOf()
Return value
A string representing the primitive value of a given String
object.
Description
The valueOf()
method of String
returns the primitive value of a String
object as a string data type. This value is equivalent to String.prototype.toString()
.
This method is usually called internally by JavaScript and not explicitly in code.
Examples
Using valueOf()
JavaScript
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var x = new String('Hello world'); console.log(x.valueOf()); // Displays 'Hello world'
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 1st Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.1. |
ECMAScript 5.1 (ECMA-262) The definition of 'String.prototype.valueOf' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'String.prototype.valueOf' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'String.prototype.valueOf' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
See also
License
© 2016 Mozilla 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/string/valueof