Nodejs Utililty Methods Date Convert

Date.prototype.dateToFormat = function(format) {
    var date = this.dateToStr();
    var yil = date.slice(0, 4);
    var ay = date.slice(4, 6);
    var gun = date.slice(6, 8);
    var saat = date.slice(8, 10);
    var dakika = date.slice(10, 12);
    var result = "";
    for (var i = 0; i < format.length; i++) {
...

Date.prototype.dateToJSON = function() {
  return this.toJSON().substring(0, 11);
};

Date.prototype.dateToStr = function() {
    var yil = this.getUTCFullYear();
    var ay = parseInt((this.getMonth() + 1) / 10) == 0 ? ("0" + (this.getMonth() + 1)) : (this.getMonth() + 1);
    var gun = parseInt(this.getDate() / 10) == 0 ? ("0" + this.getDate()) : this.getDate();
    var saat = parseInt(this.getHours() / 10) == 0 ? ("0" + this.getHours()) : this.getHours();
    var dakika = parseInt(this.getMinutes() / 10) == 0 ? ("0" + this.getMinutes()) : this.getMinutes();
    return String(yil + ay + gun + saat + dakika);

Date.prototype.dateToYMD = function() {
    var d = this.getDate();
    var m = this.getMonth() + 1;
    var y = this.getFullYear();
    return  y + (m<=9 ? '0' + m : m) +  (d <= 9 ? '0' + d : d);

Date.prototype.toAmPm = function () {
    var hours = this.getHours();
    var minutes = this.getMinutes();
    var ampm = hours >= 12 ? 'pm' : 'am';
    hours = hours % 12;
    hours = hours ? hours : 12;
    minutes = minutes < 10 ? '0' + minutes : minutes;
    return hours + ':' + minutes + ampm;
};
...

function twoDigits(d) {
    if(0 <= d && d < 10) return "0" + d.toString();
    if(-10 < d && d < 0) return "-0" + (-1*d).toString();
    return d.toString();
Date.prototype.toApiDate = function() {
    return this.getUTCFullYear() + "" + twoDigits(1 + this.getUTCMonth()) + "" + twoDigits(this.getUTCDate()); 
};
Date.prototype.toTrDate = function() {
...

Date.prototype.toCommonCase=function(){
    var xYear=this.getYear();
    xYear=xYear+1900;
    var xMonth=this.getMonth()+1;
    if(xMonth<10){
        xMonth="0"+xMonth;
    var xDay=this.getDate();
    if(xDay<10){
...

var prependZero = function(num) {
  return (num < 10)? ("0" + num) : num;
Date.prototype.toCustomFormat = function() {
  var h = this.getHours(),
      h_12hr = (h % 12),
      hh = prependZero((h_12hr == 0)? 12 : h_12hr),
      mm = prependZero(this.getMinutes()),
      ss = prependZero(this.getSeconds()),
...

Date.prototype.toDate = function(){
  return new Date(this.getFullYear(), this.getMonth(), this.getDate());

Date.prototype.toDateFormat = function (format) {
    format = format || "yyyy/mm/dd";
    return format.toLowerCase()
        .replace(/yyyy/g, this.getFullYear())
        .replace(/yy/g, this.getYear())
        .replace(/mm/g, this.getMonth2())
        .replace(/m/g, this.getMonth() + 1)
        .replace(/dd/g, this.getDate2())
        .replace(/d/g, this.getDate());
...