Moment.js Sandbox

by NibblyPig

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.24.0/moment.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.24.0/locale/en-gb.js"></script>

JavaScript

var a = "23/03/19 12:42:21.123";

var datePart = a.substring(0, a.indexOf(" "));
var timePart = a.substring(a.indexOf(" ") + 1);

var dateParts = datePart.split("/");

if (dateParts[0].length == 1) dateParts[0] = "0" + dateParts[0];
if (dateParts[1].length == 1) dateParts[1] = "0" + dateParts[1];
if (dateParts[2].length == 2) {

	var threshold = parseInt(new Date().getFullYear().toString().substring(2)) +  10;

if (parseFloat(dateParts[2]) > threshold ) {
  	dateParts[2] = "19" + dateParts[2];
  }
  else
  {
    	dateParts[2] = "20" + dateParts[2];
  }
}

alert (parseFloat(dateParts[2] + dateParts[1] + dateParts[0] + timePart.replace(/:/g, "").replace(/\./g, "")));