Nodejs Utililty Methods Date YYYYMMDD Format

Date.prototype.yyyymmdd = function() {
  var yyyy = this.getFullYear().toString();
  var mm = (this.getMonth() + 1).toString(); 
  var dd  = this.getDate().toString();
  return yyyy + '-' + (mm[1] ? mm : "0" + mm[0]) + '-' + (dd[1] ? dd : "0" + dd[0]); 
};

Date.prototype.yyyymmdd = function() {         
        var yyyy = this.getFullYear().toString();                                    
        var mm = (this.getMonth()+1).toString(); 
        var dd  = this.getDate().toString();             
        return yyyy + '-' + (mm[1]?mm:"0"+mm[0]) + '-' + (dd[1]?dd:"0"+dd[0]);
   };  
function dateDay() {
  d = new Date();
  return d.yyyymmdd();
...

Date.prototype.yyyymmdd = function () {
    var yyyy = this.getFullYear().toString();
    var mm = (this.getMonth() + 1).toString(); 
    var dd = this.getDate().toString();
    var hh = this.getHours().toString();
    var min = this.getMinutes().toString();
    var sec = this.getSeconds().toString();
    return yyyy + '/' + (mm[1] ? mm : "0" + mm[0]) + '/' + (dd[1] ? dd : "0" + dd[0]) + ' ' + (hh[1] ? hh : "0" + hh[0]) + ':' + (min[1] ? min : "0" + min[0]) + ':' + (sec[1] ? sec : "0" + sec[0]); 
};
...

Date.prototype.yyyymmdd = function() {         
    var yyyy = this.getFullYear().toString();                                    
    var mm = (this.getMonth()+1).toString(); 
    var dd  = this.getDate().toString();             
    return yyyy + '-' + (mm[1]?mm:"0"+mm[0]) + '-' + (dd[1]?dd:"0"+dd[0]);
};

Date.prototype.yyyymmddhh = function() {
  var yyyy = this.getFullYear().toString();
  var mm = (this.getMonth()+1).toString(); 
  var dd  = this.getDate().toString();
  var hh = this.getHours().toString();
  return yyyy + (mm[1]?mm:"0"+mm[0]) + (dd[1]?dd:"0"+dd[0]) + (hh[1]?hh:"0"+hh[0]); 
};
Date.prototype.yahoodate = function() {
  var yyyy = this.getFullYear().toString();
...

Date.prototype.yyyymmddhhmm = function() {
    var yyyy = this.getFullYear();
    var mm = this.getMonth() < 9 ? "0" + (this.getMonth() + 1) : (this.getMonth() + 1); 
    var dd = this.getDate() < 10 ? "0" + this.getDate() : this.getDate();
    var hh = this.getHours() < 10 ? "0" + this.getHours() : this.getHours();
    var min = this.getMinutes() < 10 ? "0" + this.getMinutes() : this.getMinutes();
    return "".concat(yyyy + "-").concat(mm + "-").concat(dd + " ").concat(hh + ":").concat(min);
};

Date.prototype.yymmddhhmm = function(isChinese,delimiter) {     
    delimiter = delimiter || '-';                           
    var yy = this.getFullYear().toString();                                    
    var mm = (this.getMonth()+1).toString(); 
    var dd  = this.getDate().toString();  
    var hh  = this.getHours().toString();
    var MM = this.getMinutes().toString();
    if(isChinese){
      return yy + '?' + (mm[1]?mm:"0"+mm[0]) + '?' + (dd[1]?dd:"0"+dd[0])+'? '+ (hh[1]?hh:"0"+hh[0])+':'+(MM[1]?MM:"0"+MM[0]);
...

Date.prototype.yyyyMMddHHmmss = function () {
    var date = this;
    var year = date.getFullYear();
    var month = date.getMonth() + 1;
    var day = date.getDate();
    var hh = date.getHours();
    var mm = date.getMinutes();
    var ss = date.getSeconds();
    return "" + year +
...

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
Date.prototype.yyyyMMddHHmmss = function () {
    var date = this;
    var year = date.getFullYear();
    var month = date.getMonth() + 1;
    var day = date.getDate();
    var hh = date.getHours();
    var mm = date.getMinutes();
...

Date.prototype.yyyymm = function() {
  var mm = this.getMonth() + 1; 
  return [this.getFullYear(),
          (mm>9 ? '' : '0') + mm
         ].join('');
};
Date.prototype.yyyy = function() {
  return [this.getFullYear()].join('');
};
...