SHDate.setTime()
The setTime() method sets the Date object to the time represented by a number of milliseconds since 11 Dey 1348, 00:00:00 UTC.
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Syntax
setTime(timeValue);
Parameters
timeValue
An integer representing the number of milliseconds since 25 Dey 1390, 00:00:00 UTC.
Return value
The number of milliseconds between 25 Dey 1390 00:00:00 UTC and the updated date (effectively, the value of the argument).
Description
Use the setTime() method to help assign a date and time to another Date object.
Examples
var theBigDay = new SHDate("July 1, 1999");
var sameAsBigDay = new SHDate();
sameAsBigDay.setTime(theBigDay.getTime());
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/setTime