The following function will pad number with leading zero(es).
function pad(number, length) {
var str = '' + number;
while (str.length < length) {
str = '0' + str;
}
return str;
}
Some code to test the function:
document.write(pad(1, 1) + '');
document.write(pad(1, 2) + '');
document.write(pad(15, 2) + '');
document.write(pad(1, 3) + '');
document.write(pad(15, 3) + '');
document.write(pad(155, 3) + '');
document.write(pad(1, 4) + '');
document.write(pad(1, 5) + '');
And the result output:
1
01
15
001
015
155
0001
00001