How to display the last modified date
So you want to display the date your page was last modified? It's just a matter of displaying the
document.lastModified property in JavaScript, but displaying it in a more user-friendly format is going to take some code.
If you're in a hurry, simply copy and paste the following code on to your web page (where you want the last modified date to appear):
<script
type="text/JavaScript"
language="JavaScript">
<!--
//
// format date as dd-mmm-yy
// example: 12-Jan-99
//
function date_ddmmmyy(date)
{
var d = date.getDate();
var m = date.getMonth() + 1;
var y = date.getYear();
// handle different year values
// returned by IE and NS in
// the year 2000.
if(y >= 2000)
{
y -= 2000;
}
if(y >= 100)
{
y -= 100;
}
// could use splitString() here
// but the following method is
// more compatible
var mmm =
( 1==m)?'Jan':( 2==m)?'Feb':(3==m)?'Mar':
( 4==m)?'Apr':( 5==m)?'May':(6==m)?'Jun':
( 7==m)?'Jul':( 8==m)?'Aug':(9==m)?'Sep':
(10==m)?'Oct':(11==m)?'Nov':'Dec';
return "" +
(d<10?"0"+d:d) + "-" +
mmm + "-" +
(y<10?"0"+y:y);
}
//
// get last modified date of the
// current document.
//
function date_lastmodified()
{
var lmd = document.lastModified;
var s = "Unknown";
var d1;
// check if we have a valid date
// before proceeding
if(0 != (d1=Date.parse(lmd)))
{
s = "" + date_ddmmmyy(new Date(d1));
}
return s;
}
//
// finally display the last modified date
// as DD-MMM-YY
//
document.write(
"This page was updated on " +
date_lastmodified() );
// -->
</script>
Listing #1 : JavaScript code. Download
lmd1.htm (0.77 KB).
- Result:
-
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How does it work?
- First we check the document.lastModified property for a valid date using "Date.parse()". This check is necessary because some web servers may not return the last modified date. Also, some browsers may suppress this information for security reasons.
- Then we simply call "date_ddmmmyy()" function to format document.lastModified into a more readable date.
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| NOTE: |
To get around Year 2000 (Y2K) issues related to the date returned by the document.lastModified property and JavaScript implementations of some browsers, we're displaying the default 2 digit year in this example. Even the "getFullYear()" function used to get the 4 digit year does not work as documented on all browsers when combined with document.lastModified.
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Applicable Keywords : HTML, Internet Explorer, Explorer 3.x, Explorer 4.x, Explorer 5.x, Internet, JavaScript, JavaScript 1.0, JavaScript 1.1, JavaScript 1.2, Netscape Navigator, Navigator 2.x, Navigator 3.x, Communicator 4.x, Netscape 6.x, World Wide Web