Valid Date in javascript

function validDate(date2)
{
// date formate 12-27-2007 mm-dd-yyyy
/* var currentTime = new Date();
var month = currentTime.getMonth() + 1
var day = currentTime.getDate();
var year = currentTime.getFullYear();
var currentDate = month + "-" + day + "-" + year;
alert(currentDate); */

var currentTime = new Date();
var currentDate = currentTime.format('m-d-Y');
//alert(currentDate);
if(trim(currentDate)!="" && trim(date2)!="")
{
var str1 = currentDate;
var str2 = date2;
var mon1 = parseInt(str1.substring(0,2),10);
var dt1 = parseInt(str1.substring(3,5),10);
var yr1 = parseInt(str1.substring(6,10),10);
var mon2 = parseInt(str2.substring(0,2),10);
var dt2 = parseInt(str2.substring(3,5),10);
var yr2 = parseInt(str2.substring(6,10),10);
var date11 = new Date(yr1, mon1, dt1);
var date22 = new Date(yr2, mon2, dt2);
if(date22 < date11) return true;
}
}