Date difference in JQuery received NAN

I am trying to calculate the days on Blur method of End Date. But I received 'NAN'.What at could be wrong? I received 'N开发者_开发技巧AN'.

$('#EndDate').blur(function () {

   var diff = dateDiff($('#StartDate').val(), $('#EndDate').val());
    alert(diff);

});

function dateDiff(startDate, endDate) {
    return endDate.getDate() - startDate.getDate();
}

.getDate() isn't defined for string objects (which is what .val() gives you), so you'll get 2 undefined variables trying to subtract one another battling it out, and undefined - undefined === NaN.

Instead, you need to get the date from both date pickers and subtract them like this:

$('#EndDate').blur(function () {
 var diff = dateDiff($('#StartDate').datepicker("getDate"), 
                     $('#EndDate').datepicker("getDate"));
 alert(diff);
});

function dateDiff(startDate, endDate) {
  if(endDate && startDate) //make sure we don't call .getTime() on a null
    return (endDate.getTime() - startDate.getTime()) / (1000*60*60*24);
  return "You must complete both dates!";
}

Also, instead of blur, I'd use the onSelect event provided, like this:

$('#EndDate').datepicker({
  onSelect: function() {
    var diff = dateDiff($('#StartDate').datepicker("getDate"), 
                        $('#EndDate').datepicker("getDate"));
    alert(diff);
  }
});

You can test it out here.

This worked for me

function calculate(start_date,end_date)         
{

  var t1= start_date ;

  var t2= end_date;

  // The number of milliseconds in one day

  var one_day=1000*60*60*24;

  //Here we need to split the inputed dates to convert them into standard format

  var x=t1.split(“/”);

  var y=t2.split(“/”);

  //date format(Fullyear,month,date)

  var date1=new Date(x[2],(x[1]-1),x[0]);

  var date2=new Date(y[2],(y[1]-1),y[0]);

  //Calculate difference between the two dates, and convert to days

  numberofDays=Math.ceil((date2.getTime()-date1.getTime())/(one_day));

  // numberofDays gives the diffrence between the two dates.

  $(‘#Input_type_text).val(numberofDays);

}