JavaScript Date Format > script

Here's an example call of what I wanted:

SomeDiv.innerText = (new Date()).format('dddd, mmmm dd, yyyy.');

This would display:

Saturday, July 16, 2005.

<script language="JavaScript">
<!--
// a global month names array
var gsMonthNames = new Array(
    'January',
    'February',
    'March',
    'April',
    'May',
    'June',
    'July',
    'August',
    'September',
    'October',
    'November',
    'December'
);

// a global day names array
var gsDayNames = new Array(
    'Sunday',
    'Monday',
    'Tuesday',
    'Wednesday',
    'Thursday',
    'Friday',
    'Saturday'
);

// the date format prototype
Date.prototype.format = function(f)
{
    if (!this.valueOf())
        return '&nbsp;';
 
    var d = this;
 
    return f.replace(/(yyyy|mmmm|mmm|mm|dddd|ddd|dd|hh|nn|ss|a/p)/gi,

        function($1)
        {
            switch ($1)
            {
            case 'yyyy': return d.getFullYear();
            case 'mmmm': return gsMonthNames[d.getMonth()];
            case 'mmm':  return gsMonthNames[d.getMonth()].substr(0, 3);
            case 'mm':   return (d.getMonth() + 1).zf(2);
            case 'dddd': return gsDayNames[d.getDay()];
            case 'ddd':  return gsDayNames[d.getDay()].substr(0, 3);
            case 'dd':   return d.getDate().zf(2);
            case 'hh':   return ((h = d.getHours() % 12) ? h : 12).zf(2);
            case 'nn':   return d.getMinutes().zf(2);
            case 'ss':   return d.getSeconds().zf(2);
            case 'a/p':  return d.getHours() < 12 ? 'a' : 'p';
            }
        } 
    );
}

// Zero-Fill
String.prototype.zf = function(l) { return '0'.string(l - this.length) + this; }

//As you can see, it depends on the string prototype, an VB-like string concatenator:

// VB-like string
String.prototype.string = function(l) { var s = '', i = 0; while (i++ < l) { s += this; } return s; }

/*
Just bear in mind there's no check for the l (length) parameter, so you must always provide a number, and finally, you must create a number prototype for it (kind of an override) in order to use it directly on numbers:
*/
Number.prototype.zf = function(l) { return this.toString().zf(l); }
//-->
</script>

from http://www.codeproject.com/useritems/dateformat.asp