JS日期相差天数

var s1 = '2012-05-12';

s1 = new Date(s1.replace(/-/g, "/"));

s1= new Date(Date.parse(s1)); 

s2 = new Date();

var days = s2.getTime() - s1.getTime();
var time = parseInt(days / (1000 * 60 * 60 * 24));