javascript - Converting Google spreadsheet date into a JS Date object?

Question

I've been going round in circles on this one... I've got a spreadsheet which holds two dates, and I need to find the number of elapsed years between the two (ie. someone's age at a given date; this is a replacement for Excel's DATEDIF).

The first step is to convert Google's serial number into a JS Date object, but there doesn't appear to be Date constructor that does this. Any ideas?

Thanks.

Answer 1

To convert a Google spreadsheet date to a javascript date :

var JSdate = Date.parse(Cell.getValue())

To convert a javascript date to a Google spreadsheet date:

function GoogleDate( JSdate ) { 
   var D = new Date(JSdate) ;
   var Null = new Date(Date.UTC(1899,11,30,0,0,0,0)) ; // the starting value for Google
   return ((D.getTime()  - Null.getTime())/60000 - D.getTimezoneOffset()) / 1440 ;
}