PHP form, checking 2 dates aren't too far apart - php

Question

I've been thrown in at the deep end at work, I grew up knowing plain HTML (mid-90's) and I've been asked to alter a form at work that's in PHP, I can alter PHP code written by others, but there's no way I could write it myself. I've altered this form to just about how I want it, but there's 1 bit I want to alter, if anyone can help it would be greatly appreciated...
been on this for 2 days searching the web and trying stuff, I have the following
<p class="quest">Date from: <input type="text" name="acc2" class="tcal" value="" /> to: <input type="text" name="acc3" class="tcal" value="" />
it uses javascript to pop up a calendar (tigra calendar) that then returns 2 dates (acc2 and acc3), the dates are in d/m/Y (DD/MM/YYYY) format (standard here in Europe/Aus/NZ).
What I'm wanting to do is get it to check if the difference is greater than 42 days (6 weeks), if it is I want it to display some text with a link (42 days or less is fine).
If I put on the page as a test:
<?php echo($acc3); ?>
then it displays 1341442800 on the page (before a date is chosen), if the user selects a date then the above number stays (not dynamic)
Is what I'm wanting possible?
If not, can it be checked on submission and pop up an alert (without the link)?
I currently use Javascript to check the form, an example is:
<script language="javascript" type="text/Javascript">
<!--
function collect() {
if(document.all.ct.value == "TempAcc")
{
if(document.all.acc7.value.length <11)
{
alert("You need to fill in your contact number with your FULL number including STD code.");
return false;
}
}
}//end function collect
//-->
</script>
any help with this would be very much appreciated, please try to be specific with any code as I'm am still very much a beginner.
Thanks in advance.

Answer 1

That works for me: Live demo on fiddle.net
// parse dates from DD/MM/YYYY to YYYY/MM/DD
var oldBegin = parseDate("03/06/2012");
var oldEnd = parseDate("07/06/2012");
// calculate difference and format to days
var diff = Math.round((oldEnd - oldBegin)/1000/60/60/24);
alert(diff);
function parseDate(str) {
var m = str.match(/^(\d{1,2})\/(\d{1,2})\/(\d{4})$/);
return (m) ? new Date(m[3], m[2]-1, m[1]) : null;
}
Edit:
Include jQuery to your webpage. It will help you with the javascript part.
Give both of your input-fields a unique id (like id="date1" and id="date2") and then get the values in javascript
$('date1').val();
$('date2').val();
The whole code should look something like that:
<script type="text/javascript">
//The code will trigger when the user leaves the second input field
$("#date2").focusout(function() {
// parse dates from DD/MM/YYYY to YYYY/MM/DD
var date1 = parseDate($('date1').val());
var date2 = parseDate($('date2').val());
// calculate difference and format to days
var diff = Math.round((date2 - date1)/1000/60/60/24);
alert(diff);
function parseDate(str) {
var m = str.match(/^(\d{1,2})\/(\d{1,2})\/(\d{4})$/);
return (m) ? new Date(m[3], m[2]-1, m[1]) : null;
}
});
</script>
You can now add some if-statements to check if one input is empty.

Answer 2

Here's two questions/answers written in PHP and Javascript
PHP
$date1 = "2007-03-24";
$date2 = "2009-06-26";
$diff = abs(strtotime($date2) - strtotime($date1));
$years = floor($diff / (365*60*60*24));
$months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
$days = floor(($diff - $years * 365*60*60*24 - $months*30*60*60*24)/ (60*60*24));
printf("%d years, %d months, %d days\n", $years, $months, $days);
Javascript
var oldBegin = ...
var oldEnd = ...
var newBegin = ...
var newEnd = new Date(newBegin + oldEnd - oldBegin);

Answer 3

Try this :
<script type="text/javascript">
function daysBetween() {
var one = new Date(2012, 0, 1); // YYYY - MM - DD
var two = new Date(2012, 5, 5); // YYYY - MM - DD
var one_day=1000*60*60*24
document.write(Math.ceil((two.getTime()-one.getTime())/(one_day))+" days")
}
</script>