While working with dates in server side javascript, I noticed some glichtes in Domino 8.5.0.
Here are some rules of thumb:

Trying to convert a text to date with @TextToTime() may work, but in my case it mixed day and month values. My solution: parse the string yourself into year, month and day parts and use @Date(y,m,d).
Note: make sure you give NUMBER values as parameter for @Date()! Otherwise @Date returns strange results like "31th dec 0001".

Getting the value of a date field with GetComponentValue() sometimes returns a string, and sometimes a javascript Date() object.
In one case it returned a Date() in the onchange event of that field. When getting the value in the onchange event of another field, GetComponetValue() returned a string.

Here is a little helper function to workaround that problem:
CAUTION: this function works in one locale only, in my case with german dates in the format DD.MM.YYYY.

function ynTextToDate(v) {
	try {
	if (typeof v != "string") return v;
	var ty = Number(v.substring(v.lastIndexOf(".")+1));
	var td = Number(v.substring(0, v.indexOf(".")));
	var tm = Number(v.substring(v.indexOf(".")+1, v.lastIndexOf(".")));
	return @Date(ty,tm,td);
	} catch (e) {
		print("ynTextToDate "+e);
	}
}

Formatting Dates

Use I18n.toString(JavaDate, pattern) with these patterns:


Symbol  	Meaning  	Presentation  	Example
G 	era designator 	Text 	AD
y 	year 	Number 	1996
M 	month in year 	Text or Number 	July (or) 07
d 	day in month 	Number 	10
h 	hour in am/pm (1-12) 	Number 	12
H 	hour in day (0-23) 	Number 	0
m 	minute in hour 	Number 	30
s 	second in minute 	Number 	55
S 	fractional second 	Number 	978
E 	day of week 	Text 	Tuesday
a 	am/pm marker 	Text 	PM
k 	hour in day (1-24) 	Number 	24
K 	hour in am/pm (0-11) 	Number 	0
z 	time zone 	Text 	Pacific Standard Time
Z 	time zone (RFC 822) 	Number 	-0800
v 	time zone (generic) 	Text 	Pacific Time
' 	escape for text 	Delimiter 	'Date='
'' 	single quote 	Literal 	'o''clock'


Examples
Pattern 	Formatted Text
"yyyy.MM.dd G 'at' HH:mm:ss vvvv" 	1996.07.10 AD at 15:08:56 Pacific Time
"EEE, MMM d, ''yy" 	Wed, July 10, '96
"h:mm a" 	12:08 PM
"hh 'o''clock' a, zzzz" 	12 o'clock PM, Pacific Daylight Time
"K:mm a, vvv" 	0:00 PM, PT
"yyyyy.MMMMM.dd GGG hh:mm aaa" 	01996.July.10 AD 12:08 PM

Auto format date and time in local format

format a date:

java.text.DateFormat.getDateInstance(java.text.DateFormat.SHORT, context.getLocale()).format(date)

format a time:

java.text.DateFormat.getTimeInstance(java.text.DateFormat.SHORT, context.getLocale()).format(date)

with

date

as a Java date and java.textDateFormat.SHORT or .MEDIUM or .LONG or .FULL.

Get weekday

Thanks to Frank van der Linden

/** * Get the ISO week date week number 
	found at http://www.domino-weblog.nl/weblogs/domblog.nsf/d6plinks/FLIN-7WMGPX
*/
Date.prototype.getWeek = function () { 
	// Create a copy of this date object 
	var target = new Date(this.valueOf()); 
	// ISO week date weeks start on monday 
	// so correct the day number 
	var dayNr = (this.getDay() + 6) % 7; 
	// Set the target to the thursday of this week so the 
	// target date is in the right year 
	target.setDate(target.getDate() - dayNr + 3); 
	// ISO 8601 states that week 1 is the week 
	// with january 4th in it 
	var jan4 = new Date(target.getFullYear(), 0, 4); 
	// Number of days between target date and january 4th 
	var dayDiff = (target - jan4) / 86400000; 
	// Calculate week number: Week 1 (january 4th) plus the 
	// number of weeks between target date and january 4th 
	var weekNr = 1 + Math.ceil(dayDiff / 7); 
	return weekNr; 
}

Count No of days between Two dates

var startDate = document3.getItemValueDate("dtFromDate")
var endDate = document3.getItemValueDate("dtToDate")


var difference = endDate.getTime() - startDate.getTime();  
difference = (Math.floor(difference/1000/60/60/24)) + 1;

Thanks, Arif Iqbal@TCSBangalore!

Comments (3)