php date convert to javascript date

Question

I have a php date and wish to echo it out in a javascript alert box:-

$day=15;
$month=8;
$year=2012;
$date_display = date("Y-m-d", mktime(0, 0, 0, $month, $day, $year));
echo $date_display; // 2012年08月15日

Then,

<a href="#" onclick="give_date(<?=$date_display;?>)"><?=$day;?></a>

The javascript function:

<script>
function give_date(value){
alert (value); 
}
</script>

Interestingly, the alert box give me "1989", which equals to 2012 minus 8 minus 15!! what shall I do!!

• Nir Alfasi: Since you use date it shouldn't make much difference, but in general, you're making a mistake here by confusing between the client-side and the server-side. The value of $date_display is calculated on the server-side while onclick is called on the client side. As for your problem, try casting to String.
• zerkms: @alfasin: nope, it's not true
• zerkms: @alfasin: the thing that "The value of $date_display is calculated on the server-side". This thing would confuse OP even more, since it's not clear what "calculated" here means: either initialization with '2012年08月15日' string value or math evaluation. And second - "As for your problem, try casting to String" --- to cast to string what? In php it is a string - makes no sense, in js - it's too late, so makes no sense as well
• Nir Alfasi: @zerkms when I said "cast to string" I meant adding quotes - my bad. But, All the first part of my comment is valid. Many programmers confuse server-side with client-side. The date is calculated on the server-side, so if the server is in US and the customer is in Europe, the browser might show that date of yesterday (from the client perspective). Confusing ? too bad, programming isn't always easy :)
• uınbɐɥs: By the way, it is better to use <?php echo $date_display; ?> rather than <?=$date_display;?>. And don't use mktime, use time.

Answer 1

Now you get: <a href="#" onclick="give_date(2012年08月15日)">15</a>, so it calculates it in browser.

the solution is simple - add quotes:

<a href="#" onclick="give_date('<?=$date_display;?>')"><?=$day;?></a>

Then you get: <a href="#" onclick="give_date('2012-08-15')">15</a>

Answer 2

You are making the client-side code show an alert with the date of the server when the page was loaded.

If you want to show the user the current time, use this:

HTML:

<a href="#" id="date">Please enable JavaScript.</a>

JavaScript:

<script type="text/javascript">
function show_date() {
 alert(new Date()); 
}
window.onload = function() {
 document.getElementById('date').innerHTML = new Date().getDay();
};
document.getElementById('date').onclick = show_date;
</script>

Answer 3

You can use jQuery if you are up for it

<a href="#" id="<?php echo $date_display; ?>">Click to get date popup</a>
$(function(){
 $('a').click(function(){
 var dt = $(this).attr('id');
 alert(dt);
 });
});

• zerkms: 2012年08月05日 is not a good candidate to be used as an id. I'd suggest to use data-date="..." instead
• asprin: @zerkms A little curious here, why not?
• asprin: Hmm...but it serves what the OP wants right? I guess it can be overlooked
• zerkms: id should begin with letter. It's how standard defines requirement to id. You may do whatever you want, but the standard is a standard. And it is a good idea to follow it