Calculate age when dates formatted dd/mm/yyyy

[[email protected]]

Does anyone have an example of how to calculate a person's age when dates are formatted dd/mm/yyyy (Australia)?

I've been going around in circles for a few hours, this is what I have so far but the age isn't being calculated correctly.


function AgeTimeOp(opdate) {

if(typeof opdate === 'object' && opdate !== null){ //test if it is an object but since null is an object also, make sure it isn't null
if(!isNaN(opdate.getMonth())){ // might be an object but not a true Date object so try to see if you can pull the month out of it

//call function to get patient DOB. Function not included here but assume a return date of 30/12/2000
var mypatdob = getparentdob();


//here I use Alpha's date conversion methods to change to MM-dd-yyyyy
//create a Date object
var myopdate = new Date();
myopdate.fromFormat(opdate,'MM-dd-yyyy');


//create a Date object
var birthDate = new Date();
birthDate.fromFormat(mypatdob,'MM-dd-yyyy');


var age = myopdate.getFullYear() - birthDate.getFullYear();
var m = myopdate.getMonth() - birthDate.getMonth();
if (m < 0 || (m === 0 && myopdate.getDate() < birthDate.getDate())) {
age = age - 1;
}

return age;
}
}
else {
return '';
}
}

All help appreciated.

[Ted Giles]

Re: Calculate age when dates formatted dd/mm/yyyy

I don't use Alpha Web, (strictly DT) but is this not in the field formatting?

[armasoft]

Re: Calculate age when dates formatted dd/mm/yyyy

I did a google search on 'javascript age dd/mm/yy' and this was the first result https://stackoverflow.com/questions/...yy-date-format

[[email protected]]

Re: Calculate age when dates formatted dd/mm/yyyy

Thanks, I had tried that one and many other online samples but I just can't get any to work with a calculated field. What has me stumped is that in Alpha's interactive window the code works but as soon as I put it into a function which is called by the calculated field I get NaN.

Here is the function where I have hardcoded dates in dd/mm/yyyy format. If anyone wants to try, you will see it returns NaN. Then paste the code into the interactive window and it returns a value of 17 which is correct.

function AgeTimeOp() {

var mypatdob = "20/12/2000";
var opdate = "19/12/2018";

var birthDate = new Date(mypatdob.replace(/(\d{2})-(\d{2})-(\d{4})/, "$2/$1/$3"));
var myopdate = new Date(opdate.replace(/(\d{2})-(\d{2})-(\d{4})/, "$2/$1/$3"));

var age = myopdate.getFullYear() - birthDate.getFullYear();

var m = myopdate.getMonth() - birthDate.getMonth();
if (m < 0 || (m === 0 && myopdate.getDate() < birthDate.getDate())) {
age = age - 1;
}

return age;
}

[Garry Flanigan]

Re: Calculate age when dates formatted dd/mm/yyyy

I also remember having the NaN problem but maybe try the following. 2 fields, one called say DateOfBirth of type date and a numeric field called Age that is calculated with formula myCustomAge(DateOfBirth).

You have a javascript function:

function myCustomAge(dob) {


if(typeof dob == "string")
{
var dateparts = dob.split("/");
var userday = dateparts[0];
var usermonth = dateparts[1];
var useryear = dateparts[2];
}
else
{
var userday = dob.getDate();
var usermonth = dob.getMonth() + 1; // getMonth returns 0 - 11, January is 0, etc, so need to add 1!
var useryear = dob.getFullYear();
}


var d = new Date();
var curday = d.getDate();
var curmonth = d.getMonth() + 1; // getMonth returns 0 - 11, January is 0, etc, so need to add 1!
var curyear = d.getFullYear();

if((curmonth < usermonth) || ( (curmonth == usermonth) && (curday < userday)))
{
var age = curyear - useryear - 1;
}
else
{
var age = curyear - useryear;
}

return age;
}

[Jay Talbott]

Re: Calculate age when dates formatted dd/mm/yyyy

Alternatively, if an Ajax callback isn't too expensive, why not send the date of birth back to the server and use Xbasic to determine the age. This is from the interactive window but would be very easy to use in an Ajax callback:

dim dobc as c
dobc = "17/01/1957"

dim dobd as d
dim yearsOld as n
yearsOld = age(ctod(substr(dobc,4,2) + "/" + substr(dobc,1,2) + "/" + substr(dobc,7,4)))

?yearsOld
= 61

Hope that helps.
Jay

[mikeallenbrown]

Re: Calculate age when dates formatted dd/mm/yyyy

I use moment.js for handling dates.

Moment JS

For your situation I wrote...

var _date = moment('23/09/1978','DD/MM/YYYY').format('YYYY-MM-DD');

var years = moment().diff(_date, 'years');

alert(years);

...which gave me an alert of 40.

Another method is to let the database do the calculation when the user saves the data. In MS SQL the computed column specification is...

(datediff(day,[COLUMN_NAME],getdate())/(365))

[Davidk]

Re: Calculate age when dates formatted dd/mm/yyyy

It's unclear if you're working with date strings or date objects. You should decide if you want to handle this in your age function... or ensure that your age function always gets the same data type.

In your 2nd example you're doing some wild stuff with replace... which I don't think is needed.

Alpha has a couple of excellent methods for taming dates. .toFormat() and .fromFormat. This example takes the same StackOverflow answer you've used, using dates strings, and returns a date to the Calculated Field Expression...

function AgeTimeOp() {

	var mypatdob = "20/12/2000"; 
	var opdate = "19/12/2018";

	var birthDate = new Date();
	birthDate.fromFormat(mypatdob,"dd/MM/yyyy");
	
	var myopdate = new Date();
	myopdate.fromFormat(opdate,"dd/MM/yyyy");

	var age = myopdate.getFullYear() - birthDate.getFullYear();

	var m = myopdate.getMonth() - birthDate.getMonth();
	if (m < 0 || (m === 0 && myopdate.getDate() < birthDate.getDate())) {
		age = age - 1;
	}
	
	return age;
	
}

This takes date strings and converts them to date objects using .fromFormat(). The rest of your calc now works... and the Calculated Field Expression has an age.

[[email protected]]

Re: Calculate age when dates formatted dd/mm/yyyy

Thanks David,

I was close in my initial post which used Alpha's fromformat methods but thought I had to change the format to MM/dd/yyyy.

For everyone's benefit here is the code that worked for me. For some reason I couldn't get it to work when passing the opdate value into the function, the opdate object was always today regardless of the value in the opdate field. So I only used the opdate field value (see operationate var below) in my if statement to test that the field wasn't null etc, then I set the opdate var using the getvalue method.

function AgeTimeOp(operationdate) {

if(typeof operationdate === 'object' && operationdate !== null){ //test if it is an object but since null is an object also, make sure it isn't null
if(!isNaN(operationdate.getMonth())){ // might be an object but not a true Date object so try to see if you can pull the month out of it

var mypatdob = getparentdob(); //calls function to get patient DOB
var opdate = {grid.object}._getValue('D','OPDATE');

var birthDate = new Date();
birthDate.fromFormat(mypatdob,"dd/MM/yyyy");

var myopdate = new Date();
myopdate.fromFormat(opdate,"dd/MM/yyyy");

var age = myopdate.getFullYear() - birthDate.getFullYear();

var m = myopdate.getMonth() - birthDate.getMonth();
if (m < 0 || (m === 0 && myopdate.getDate() < birthDate.getDate())) {
age = age - 1;
}

return age;
}

}
else {
return '';
}
}