moment string back to moment object code example

Example 1: moment format heure

var time = "15:30:00";
var formatted = moment(time, "HH:mm:ss").format("LT");
console.log(formatted); 
//it will return 3:30 PM

Example 2: moment diff

var a = moment([2007, 0, 29]);
var b = moment([2007, 0, 28]);
a.diff(b, 'days') // 1