Question

What is the difference between

  new Date(2013,0,1)

and

  Date.parse("2013-1-1")

that breaks http://api.jqueryui.com/datepicker/#method-setDate

Here is jsfiddle http://jsfiddle.net/tawVx/4/

Answer 1

Date.parse() returns the number of milliseconds elapsed since January 1st, 1970, 00:00:00 UTC, not a Date object.

setDate() takes either a Date object or a string, not a number of milliseconds elapsed since the epoch.

The following code would work:

$("#datepicker").datepicker("setDate", new Date(Date.parse("2013-01-01")));