Javascript code to calculate age from a Date Of Birth field

[Hovik]

Code: Select all

var dateNow = new Date();
var dateDOB = new Date(fields.DOB.value);

var yearNow = dateNow.getFullYear(); //getting current year
var mnthNow = dateNow.getMonth();
var dayNow = dateNow.getDate();

var yearDOB = dateDOB.getFullYear(); //getting dob year
var mnthDOB = dateDOB.getMonth();
var dayDOB = dateDOB.getDate();

//calculating age
if ( (mnthNow > mnthDOB) || (mnthNow==mnthDOB && dayNow >= dayDOB) )
   {fields.AGE.value = yearNow - yearDOB;}
else
   {fields.AGE.value = yearNow - yearDOB - 1;}

[AJDulk]

If you want to check if a Date field is populated or not then use the following:

Code: Select all

if (fields.DATE_FIELD_NAME.displayValue) { ... }

instead of:

Code: Select all

if (fields.DATE_FIELD_NAME.value) { ... }

There is a problem when using value and someone fills in the 1st of January 1970, value gives a 0 back and therefore JavaScript sees it as being empty (false instead of true since 0 and null is false and anything else is true).

--

For some reason using

Code: Select all

new Date.getFullYear()

throws an error, instead use

Code: Select all

new Date().getFullYear()

to get the current year without having to create any extra variables.

To get the current date you can also use

Code: Select all

Date.now()

which is a little easier than doing

Code: Select all

system.variables.$SYSTEM_DATE.value

[AJDulk]

To convert to number of days use:

Code: Select all

function getNumberOfDays(dateInMilliseconds) {
	return Math.floor(dateInMilliseconds / 84600000);
}

Note that JavaScript in Ebase automatically gives a date in milliseconds.
Example of use:

Code: Select all

if (getNumberOfDays(fields.END_DATE.value - fields.START_DATE.value) > 14) {
  event.owner.addErrorMessage("Maximum number of days exceeded!!!");
}