jQuery设置数字格式

Question

I'm using JQuery and I'm having a problem trying to sort out how to increase a number.

The record number is something like 1364-14-1234.

The number format works like this: 1364 - Member number 14 - Year in 2 digit format 1234 - in the number which needs to be increased.

The problem is how do I add a leading zero to the number to keep a 4 digit number if the number is 0123.

<div id="member_id">1364-14-0001</div>

var data = $('#member_id').text();
var arr = data.split('-');
var num = arr[2];
num++;
$("#member_id").html(arr[0] + " - " + arr[1] + " - " + num);

My JSfiddle

Answer 1

Something like this maybe

function pad(numb, len) {
    while (numb.toString().length < len) numb = '0' + numb;
    return numb;
}

$('#member_id').text(function(_, txt) {
    var arr = txt.split('-'),
        len = arr[2].length;

    arr[2] = pad(+(arr[2]) + 1, len);
    return arr.join('-')
});

FIDDLE