Javascript Date Validation / Comparison

Problem:
User enters two dates, say start date and end date, then we need to alert him if the start date is greater than end date.

Solution:
Assume we are getting the date to the input field using a datepicker.

First we have to convert the string into Date() object using
var dObj = new Date(year, month, date); (also note: the month value range from 0 to 11)
and we can compare the dates.

Example:
var x = document.formName;

//assume the date format is YYYY/MM/DD
var sDate1 = x.start_date.value;
var sDate = new Date(sDate1.split('/')[0], parseInt((sDate1.split('/')[1])-1), sDate1.split('/')[2]);
var eDate1 = x.end_date.value;
var eDate = new Date(eDate1.split('/')[0], parseInt((eDate1.split('/')[1])-1), eDate1.split('/')[2]);
if(eDate >= sDate)
{
    alert("End date is greater than start date; please try again....");
    return false;
}

-

How to add month, days, years in a date

<?php
$day1 = "2008/10/20";

//add month
$day2 = date("Y/m/d", strtotime("+2 months", strtotime($day1)));
//"2008/12/20"
$day2 = date("Y/m/d", strtotime("+3 months", strtotime($day1)));
//"2009/01/20"
//add days
$day2 = date("Y/m/d", strtotime("+5 days", strtotime($day1))); //"2008/10/25"
$day2 = date("Y/m/d", strtotime("+20 days", strtotime($day1))); //"2008/11/09"
//years
$day2 = date("Y/m/d", strtotime("+2 years", strtotime($day1))); //"2010/10/20"
?>
Also we can add weeks.

how to change month number to month name?

how to change month no to month name?
link 02 to february or Feb...

function month_name($month_no)
{
$timestmp = mktime(0,0,0,$month_no,1,2008);
return date("M",$timestmp);
}

echo month_name(10); //will return October
?>


Cheers!

No of days between two dates in php

We can find the no days between two dates using PHP....
There are 2 methods:

1) Split the date and subtract
$date1 = "2008-05-18";
$arr = explode('-',$date1); //split the date
$date2 = $arr[2]; //stores 18
$cur_date = date("d"); // current date
echo "Difference: ";
echo $cur_date-$date2;



2) Convert dates into timestamp, subtract and then convert as we want
$date1 = "2008-04-18";
$to_day = date("Y-m-d"); //current date
$day_diff = (strtotime($to_day)-strtotime($date1))/86400; //60*60*24=86400
echo $day_diff;

//change the divider(864000 to get ur corresponding difference
$hour_difference = (strtotime($to_day)-strtotime($date1))/3600; //60*60=3600
$week_diff = (strtotime($to_day)-strtotime($date1))/604800; //60*60*24*7=604800