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The valueOf()
method returns the primitive value of a Date
object.
Syntax
dateObj.valueOf()
Return value
The number of milliseconds between 1 January 1970 00:00:00 UTC and the given date.
Description
The valueOf()
method returns the primitive value of a Date
object as a number data type, the number of milliseconds since midnight 01 January, 1970 UTC.
This method is functionally equivalent to the Date.prototype.getTime()
method.
This method is usually called internally by JavaScript and not explicitly in code.
Examples
Using valueOf()
var x = new Date(56, 6, 17); var myVar = x.valueOf(); // assigns -424713600000 to myVar
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 'Date.prototype.valueOf' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Date.prototype.valueOf' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Date.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) |