on tme from date code example

Example 1: format date js

var options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
var today  = new Date();

console.log(today.toLocaleDateString("en-US")); // 9/17/2016
console.log(today.toLocaleDateString("en-US", options)); // Saturday, September 17, 2016

 // For custom format use
 date.toLocaleDateString("en-US", { day: 'numeric' })+ "-"+ date.toLocaleDateString("en-US", { month: 'short' })+ "-" + date.toLocaleDateString("en-US", { year: 'numeric' }) // 16-Nov-2019

Example 2: calculate total time from start and end datetime

var date1 = new Date('2019-02-27T23:34:25');
var date2 = new Date('2019-02-28T15:55:38');
var ElapsedSeconds = (date2 - date1) / 1000;
// var ElapsedHours = ElapsedSeconds / 3600;