Using JS document.lastModified function

[axcohn]

Hello,

I am not a programmer, and I'm trying to use any of several JS scripts I've found on the net to display an HTML file's last-modified date in a Mac environment (Unix servers). The first script (see script 1 below) seems to display the current system date, rather than the file's last-modified date. The other two scripts (see scripts 2 and 3 below) produce a blank line in both Safari and Firefox.

I've tried both embedding the JS in the HTML file and referencing it from an external file. There's no difference in the results. I'd prefer to reference an external JS file, so I can easily affect multiple pages in the small site I'm creating (4 pages).

The calling code is shown below:

<div id="footer">
<p><script type="text/JavaScript" src="../savedate.js"></script>
<noscript>
  Updated June, 2008
</noscript>

<br>
	Comments and corrections: <a href="[email_alias_here]?subject=Comment or correction on workflow page titled: ">contact the webmaster</a></p>
	<!-- Footer end -->
	</div>

Is it possible that the server does not have the module that supports the methods that the JS is using?
------------------------------

Script 1: appears to display current date

<!--
// Y2K READY-USE GetFullYear
// DAY Names Javascript is funny Starts the numbering with Zero this array translates to 0...6 to the days of the week
// REMEMBER Arrays have to be written all on ONE(1) line to work
var stampdays = new Array( "Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday");
// Month Names - Guess what this array does. 0..11 to the system clock month
var stampmonths = new Array( "January","February","March","April","May","June","July","August","September","October","November","December");
// GRABS the Date info from your System clock when your Browser reads enters the page.
var thedate = new Date();
//Gets the Translated Arrays written to the webpage for viewing. Remember you can use this for other things, too
document.write(stampdays[ thedate.getDay()] + ", " + stampmonths[ thedate.getMonth()] + " " + thedate.getDate() + ", " + thedate.getFullYear());
// -->

---------------
Script 2: produces blank line

<!-- Hide from old browsers
//
// 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( 
  "Last updated: " + 
  date_lastmodified() );

// -->

------------------
Script 3: produces blank line

<!--
lastmod = document.lastModified     // get string of last modified date
lastmoddate = Date.parse(lastmod)   // convert modified string to date
if (lastmoddate == 0) {               // unknown date (or January 1, 1970 GMT)
  document.writeln("Last Modified: Unknown")
  } else {
    document.writeln("Last Modified: " + lastmod)
    }
// -->

[curtiss]

Originally Posted by axcohn

Is it possible that the server does not have the module that supports the methods that the JS is using?

Not very likely. It would be more likely that Safari and Firefox don't support the lastModified propery, but I doubt that, too.

I would suspect the most likely culprit is probably a minor error in the javascript code. Please use the javascript console in Firefox to examine the page for any errors or warnings that are being generated.

[axcohn]

Just because I had no other ideas, I looked again at my test page in both FF and Safari. Today, the JS works as expected in FF, but not Safari. I viewed both the FF error console and Firebug, and neither reported an error. There is, apparently, something special required for Safari to process the JS — I just don't know what.

[axcohn]

I've finally come to understand (thanks, Rob Weaver) that the root problems are these:

• I should be using server-side includes; JS just deals with client-side information (unless the server has a compiler for executing JS on the server)
• I'm not sure whether the corporate web servers are configured to enable SSIs for the directory where the microsite is hosted.

I've contacted my server support group about this, giving them some very specific questions about the configuration of their mod_include module.