How to Pad a Number with Leading Zero

Here's a slightly more compact method

event.value = ("0000000000" + event.value).slice(-10);

or

event.value = util.printf("%010d", event.value);

This could be used as either a format or validation script

As validation script of field where you input number use this:

function zeroes(number, length) {
var str = "" + number;
while(str.length < length){
str = "0" + str;}
return str;}
if(event.value != "")
event.value = zeroes(event.value,10);