//计算日期相减天数
function DateMinus(sDate){
var sdate = new Date(sDate.replace(/-/g, "/"));
var now = new Date();
var days = now.getTime() - sdate.getTime();
var day = parseInt(days / (1000 * 60 * 60 * 24));
return day;
}
原文：http://www.cnblogs.com/yuzhengbo/p/6429400.html