Date.prototype.toJSON()
  The toJSON() method returns a string representation of
  the Date object.
Syntax
toJSON()
Return value
A string representation of the given date.
Description
  Date instances refer to a specific point in time. Calling
  toJSON() returns a string (using toISOString()) representing the Date object's value. This method is
  generally intended to, by default, usefully serialize Date objects during
  JSON serialization.
Examples
Using toJSON()
var jsonDate = (new Date()).toJSON();
var backToDate = new Date(jsonDate);
console.log(jsonDate); //2015-10-26T07:46:36.611Z
Specifications
| Specification | 
|---|
| ECMAScript Language Specification # sec-date.prototype.tojson | 
Browser compatibility
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