function DateAdd(objDate, strInterval, intIncrement)
    {
        if(typeof(objDate) == "string")
        {
            objDate = new Date(objDate);
 
            if (isNaN(objDate))
            {
                throw("DateAdd: Date is not a valid date");
            }
        }
        else if(typeof(objDate) != "object" || objDate.constructor.toString().indexOf("Date()") == -1)
        {
            throw("DateAdd: First parameter must be a date object");
        }
 
        if(
        strInterval != "M"
        && strInterval != "D"
        && strInterval != "Y"
        && strInterval != "h"
        && strInterval != "m"
        && strInterval != "uM"
        && strInterval != "uD"
        && strInterval != "uY"
        && strInterval != "uh"
        && strInterval != "um"
        && strInterval != "us"
        )
        {
            throw("DateAdd: Second parameter must be M, D, Y, h, m, uM, uD, uY, uh, um or us");
        }
 
        if(typeof(intIncrement) != "number")
        {
            throw("DateAdd: Third parameter must be a number");
        }
 
        switch(strInterval)
        {
            case "M":
            objDate.setMonth(parseInt(objDate.getMonth()) + parseInt(intIncrement));
            break;
 
            case "D":
            objDate.setDate(parseInt(objDate.getDate()) + parseInt(intIncrement));
            break;
 
            case "Y":
            objDate.setYear(parseInt(objDate.getYear()) + parseInt(intIncrement));
            break;
 
            case "h":
            objDate.setHours(parseInt(objDate.getHours()) + parseInt(intIncrement));
            break;
 
            case "m":
            objDate.setMinutes(parseInt(objDate.getMinutes()) + parseInt(intIncrement));
            break;
 
            case "s":
            objDate.setSeconds(parseInt(objDate.getSeconds()) + parseInt(intIncrement));
            break;
 
            case "uM":
            objDate.setUTCMonth(parseInt(objDate.getUTCMonth()) + parseInt(intIncrement));
            break;
 
            case "uD":
            objDate.setUTCDate(parseInt(objDate.getUTCDate()) + parseInt(intIncrement));
            break;
 
            case "uY":
            objDate.setUTCFullYear(parseInt(objDate.getUTCFullYear()) + parseInt(intIncrement));
            break;
 
            case "uh":
            objDate.setUTCHours(parseInt(objDate.getUTCHours()) + parseInt(intIncrement));
            break;
 
            case "um":
            objDate.setUTCMinutes(parseInt(objDate.getUTCMinutes()) + parseInt(intIncrement));
            break;
 
            case "us":
            objDate.setUTCSeconds(parseInt(objDate.getUTCSeconds()) + parseInt(intIncrement));
            break;
        }
        
        return objDate;
    }
    
//    // String date method
//    var mydate = '6/20/2008';
//    mydate = DateAdd(mydate, "D", -10);
//    alert("The date is now: " + mydate.getDate());

//    // Date object method
//    var mydate = new Date();
//    mydate = DateAdd(mydate, "D", 5);
//    alert("The date is now: " + mydate.getDate());

    ///date object prototype
    Date.prototype.Add = function(strInterval, intIncrement)
    {
        if(
        strInterval != "M"
        && strInterval != "D"
        && strInterval != "Y"
        && strInterval != "h"
        && strInterval != "m"
        && strInterval != "uM"
        && strInterval != "uD"
        && strInterval != "uY"
        && strInterval != "uh"
        && strInterval != "um"
        && strInterval != "us"
        )
        {
            throw("DateAdd: Second parameter must be M, D, Y, h, m, uM, uD, uY, uh, um or us");
        }
 
        if(typeof(intIncrement) != "number")
        {
            throw("DateAdd: Third parameter must be a number");
        }
 
        switch(strInterval)
        {
            case "M":
            this.setMonth(parseInt(this.getMonth()) + parseInt(intIncrement));
            break;
 
            case "D":
            this.setDate(parseInt(this.getDate()) + parseInt(intIncrement));
            break;
 
            case "Y":
            this.setYear(parseInt(this.getYear()) + parseInt(intIncrement));
            break;
 
            case "h":
            this.setHours(parseInt(this.getHours()) + parseInt(intIncrement));
            break;
 
            case "m":
            this.setMinutes(parseInt(this.getMinutes()) + parseInt(intIncrement));
            break;
 
            case "s":
            this.setSeconds(parseInt(this.getSeconds()) + parseInt(intIncrement));
            break;
 
            case "uM":
            this.setUTCMonth(parseInt(this.getUTCMonth()) + parseInt(intIncrement));
            break;
 
            case "uD":
            this.setUTCDate(parseInt(this.getUTCDate()) + parseInt(intIncrement));
            break;
 
            case "uY":
            this.setUTCFullYear(parseInt(this.getUTCFullYear()) + parseInt(intIncrement));
            break;
 
            case "uh":
            this.setUTCHours(parseInt(this.getUTCHours()) + parseInt(intIncrement));
            break;
 
            case "um":
            this.setUTCMinutes(parseInt(this.getUTCMinutes()) + parseInt(intIncrement));
            break;
 
            case "us":
            this.setUTCSeconds(parseInt(this.getUTCSeconds()) + parseInt(intIncrement));
            break;
        }
        return this;
    }
    
//    var mydate = new Date('6/20/2008');
//    alert(mydate.Add("D", 10));

///returns the datediff as integer
function DateDiff(fromDate, toDate)
{
    var datDiff = Math.floor((toDate - fromDate)/(24*60*60*1000));
    
    return datDiff;
}

///returns the datediff as decimal number including hour differences
function DateDiffDecimal(fromDate, toDate) {
    var datDiff = ((toDate - fromDate) / (24 * 60 * 60 * 1000));

    return datDiff;
}

////date formats ////////////////////////////

////var now = new Date();

////now.format("m/dd/yy");
////// Returns, e.g., 6/09/07

////// Can also be used as a standalone function
////dateFormat(now, "dddd, mmmm dS, yyyy, h:MM:ss TT");
////// Saturday, June 9th, 2007, 5:46:21 PM

////// You can use one of several named masks
////now.format("isoDateTime");
////// 2007-06-09T17:46:21

////// ...Or add your own
////dateFormat.masks.hammerTime = 'HH:MM! "Can\'t touch this!"';
////now.format("hammerTime");
////// 17:46! Can't touch this!

////// When using the standalone dateFormat function,
////// you can also provide the date as a string
////dateFormat("Jun 9 2007", "fullDate");
////// Saturday, June 9, 2007

////// Note that if you don't include the mask argument,
////// dateFormat.masks.default is used
////now.format();
////// Sat Jun 09 2007 17:46:21

////// And if you don't include the date argument,
////// the current date and time is used
////dateFormat();
////// Sat Jun 09 2007 17:46:22

////// You can also skip the date argument (as long as your mask doesn't
////// contain any numbers), in which case the current date/time is used
////dateFormat("longTime");
////// 5:46:22 PM EST

////// And finally, you can convert local time to UTC time. Either pass in
////// true as an additional argument (no argument skipping allowed in this case):
////dateFormat(now, "longTime", true);
////now.format("longTime", true);
////// Both lines return, e.g., 10:46:21 PM UTC

////// ...Or add the prefix "UTC:" to your mask.
////now.format("UTC:h:MM:ss TT Z");
////// 10:46:21 PM UTC

/*
 * Date Format 1.2.2
 * (c) 2007-2008 Steven Levithan <stevenlevithan.com>
 * MIT license
 * Includes enhancements by Scott Trenda <scott.trenda.net> and Kris Kowal <cixar.com/~kris.kowal/>
 *
 * Accepts a date, a mask, or a date and a mask.
 * Returns a formatted version of the given date.
 * The date defaults to the current date/time.
 * The mask defaults to dateFormat.masks.default.
 */

var dateFormat = function () {
	var	token = /d{1,4}|m{1,4}|yy(?:yy)?|([HhMsTt])\1?|[LloSZ]|"[^"]*"|'[^']*'/g,
		timezone = /\b(?:[PMCEA][SDP]T|(?:Pacific|Mountain|Central|Eastern|Atlantic) (?:Standard|Daylight|Prevailing) Time|(?:GMT|UTC)(?:[-+]\d{4})?)\b/g,
		timezoneClip = /[^-+\dA-Z]/g,
		pad = function (val, len) {
			val = String(val);
			len = len || 2;
			while (val.length < len) val = "0" + val;
			return val;
		};

	// Regexes and supporting functions are cached through closure
	return function (date, mask, utc) {
		var dF = dateFormat;

		// You can't provide utc if you skip other args (use the "UTC:" mask prefix)
		if (arguments.length == 1 && (typeof date == "string" || date instanceof String) && !/\d/.test(date)) {
			mask = date;
			date = undefined;
		}

		// Passing date through Date applies Date.parse, if necessary
		date = date ? new Date(date) : new Date();
		if (isNaN(date)) throw new SyntaxError("invalid date");

		mask = String(dF.masks[mask] || mask || dF.masks["default"]);

		// Allow setting the utc argument via the mask
		if (mask.slice(0, 4) == "UTC:") {
			mask = mask.slice(4);
			utc = true;
		}

		var	_ = utc ? "getUTC" : "get",
			d = date[_ + "Date"](),
			D = date[_ + "Day"](),
			m = date[_ + "Month"](),
			y = date[_ + "FullYear"](),
			H = date[_ + "Hours"](),
			M = date[_ + "Minutes"](),
			s = date[_ + "Seconds"](),
			L = date[_ + "Milliseconds"](),
			o = utc ? 0 : date.getTimezoneOffset(),
			flags = {
				d:    d,
				dd:   pad(d),
				ddd:  dF.i18n.dayNames[D],
				dddd: dF.i18n.dayNames[D + 7],
				m:    m + 1,
				mm:   pad(m + 1),
				mmm:  dF.i18n.monthNames[m],
				mmmm: dF.i18n.monthNames[m + 12],
				yy:   String(y).slice(2),
				yyyy: y,
				h:    H % 12 || 12,
				hh:   pad(H % 12 || 12),
				H:    H,
				HH:   pad(H),
				M:    M,
				MM:   pad(M),
				s:    s,
				ss:   pad(s),
				l:    pad(L, 3),
				L:    pad(L > 99 ? Math.round(L / 10) : L),
				t:    H < 12 ? "a"  : "p",
				tt:   H < 12 ? "am" : "pm",
				T:    H < 12 ? "A"  : "P",
				TT:   H < 12 ? "AM" : "PM",
				Z:    utc ? "UTC" : (String(date).match(timezone) || [""]).pop().replace(timezoneClip, ""),
				o:    (o > 0 ? "-" : "+") + pad(Math.floor(Math.abs(o) / 60) * 100 + Math.abs(o) % 60, 4),
				S:    ["th", "st", "nd", "rd"][d % 10 > 3 ? 0 : (d % 100 - d % 10 != 10) * d % 10]
			};

		return mask.replace(token, function ($0) {
			return $0 in flags ? flags[$0] : $0.slice(1, $0.length - 1);
		});
	};
}();

// Some common format strings
dateFormat.masks = {
	"default":      "ddd mmm dd yyyy HH:MM:ss",
	shortDate:      "m/d/yy",
	mediumDate:     "mmm d, yyyy",
	longDate:       "mmmm d, yyyy",
	fullDate:       "dddd, mmmm d, yyyy",
	shortTime:      "h:MM TT",
	mediumTime:     "h:MM:ss TT",
	longTime:       "h:MM:ss TT Z",
	isoDate:        "yyyy-mm-dd",
	isoTime:        "HH:MM:ss",
	isoDateTime:    "yyyy-mm-dd'T'HH:MM:ss",
	isoUtcDateTime: "UTC:yyyy-mm-dd'T'HH:MM:ss'Z'"
};

// Internationalization strings
dateFormat.i18n = {
	dayNames: [
		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat",
		"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
	],
	monthNames: [
		"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
		"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"
	]
};

// For convenience...
Date.prototype.format = function (mask, utc) {
	return dateFormat(this, mask, utc);
};

///converts a string to date according
function ToDate(strDate) {
    //debugger
    var dt = null;

    if (typeof (strDate) == 'string') {
        if (strDate && strDate != '') {
            //if (strFormat == "dd/MM/yyyy")
            var dtY = strDate.substring(6, 10);
            var dtD = strDate.substring(0, 2);
            var dtM = strDate.substring(3, 5);

            dt = new Date(dtM + '/' + dtD + '/' + dtY);
        }
    }
    else {
        dt = strDate;
    }

    return dt;
}