how to set hours minutes seconds from date in javascript code example

Example 1: javascript hours minutes seconds

var myDate = new Date().toTimeString().replace(/.*(\d{2}:\d{2}:\d{2}).*/, "$1");
    console.log(myDate)
//using regex

Example 2: javascript hours minutes seconds

String.prototype.toHHMMSS = function () {
    var sec_num = parseInt(this, 10); // don't forget the second param
    var hours   = Math.floor(sec_num / 3600);
    var minutes = Math.floor((sec_num - (hours * 3600)) / 60);
    var seconds = sec_num - (hours * 3600) - (minutes * 60);

    if (hours   < 10) {hours   = "0"+hours;}
    if (minutes < 10) {minutes = "0"+minutes;}
    if (seconds < 10) {seconds = "0"+seconds;}
    return hours+':'+minutes+':'+seconds;
}