Problem with javascript dates

[Sree Mami]

Hi all

I am using datetimepicker tool and getting dates from it into text fields. I have two dates I have to compare these two dates, which are in the text field and have to return difference of dates and alert message if start date is greater than end date and all...

I am using javascript function

 
 
var startdate=new Date();
var duedate=new Date();
startdate=document.form.tf1.value;
duedate=document.form.tf1.value;
var sdate=startdate.getTime();
 
   

Here I am getting error saying; startdate.getTime is not a valid function. Can anyone help me out how to retrieve the Textfield value as Date object

[Eric Pascarello]

Because you are using a string. Remember that JavaScript has loose variables. Just because you initally set it to a Date() object does not mean that is what it will be when you set it with something else.

The proper way is to do:

var date1 = new Date(document.formName.elementName.value);

and to compare it is as simple as

var diff = date2 - date1;

Eric

[Sree Mami]

Hi Eric

I tried using

var d1=new Cal(document.formname.elementname.value)

But when I am printing d1 I am getting invalid date.

How to solve this problem?

Even I have one more doubt when I add an integer value to my d1 I need to increment the date by those integer number of days.

To generate these days I am using datetimepicker.js tool

[Christophe Verré]

Why "new Cal" ?
Eric proposed "new Date"

[Sree Mami]

Sorry it was new Date(document.formname.elementname.value) it was a mistake in my typing

[Jaikiran Pai]

Even I have one more doubt when I add an integer value to my d1 I need to increment the date by those integer number of days.

You can do this:

function incrementDate() {
 var myDate = new Date("July 21, 1983 01:15:00");
 var incrementedDate = myDate.getDate() + 1;
 alert("After incrementing the date is: " + incrementedDate);
}

[Jaikiran Pai]

But when I am printing d1 I am getting invalid date.

Post an example

[Eric Pascarello]

But when I am printing d1 I am getting invalid date.

I bet you are using DD/MM/YYYY instead of MM/DD/YYYY

Look at the function I posted here: http://www.webdeveloper.com/forum/showthread.php?p=384325#post384325

Eric

[Sree Mami]

Then, can't we use UK Date format for date calculations?

[Eric Pascarello]

No, JavaScript only handles certain date formats and that is not one of them as you already have seen. Hence why I have given you all of this code that does the work for you. It is not that hard to use it!

Eric

[Sree Mami]

Hi Eric

I am already using that code which you have given me and it is working fine. Just I want to know more information on, why it is in US format but not in UK format when comparing/working on dates dates!

I posted my last reply just to improve my knowledge in javascript and the link which you have given me solved all my troubles..

Thanks for all your timely help...

[Eric Pascarello]

The date constructor only accepts certain formats. They are

Date() - Used for current date or create an instance of the date object
Date(dateString) - Sepcify a Date/ String format is "month day, year hours:minutes:seconds" or "MM/DD/YY HH:MM:SS".
Date(year, month, day, hours, minutes, seconds) - Create an instance of date with the specified values. Can be just (year, month, date)

Eric

[Sree Mami]

Hi Eric

The below function returns incrementedDate value in UTC format, if at all I want to change it to US format, how should I be doing that?

 
function incrementDate() { var myDate = new Date("July 21, 1983 01:15:00"); var incrementedDate = myDate.getDate() + 1; alert("After incrementing the date is: " + incrementedDate);}
 
   

Actually I have to add number of days to a day and need to display the new date in US/UK Format, but when I am using this function I am getting the value in UTC format, how can I convert then?

Please help me out..
[ August 28, 2006: Message edited by: Sree Mami ]