原生Javascript:

new Date().toLocaleString('zu-ZA').slice(0,10).replace(/-/g,'');

我经常使用的一段修改代码:

Date.prototype.yyyymmdd = function() {
  var mm = this.getMonth() + 1; // getMonth() is zero-based
  var dd = this.getDate();

  return [this.getFullYear(),
          (mm>9 ? '' : '0') + mm,
          (dd>9 ? '' : '0') + dd
         ].join('');
};

var date = new Date();
date.yyyymmdd();

下面是一种更通用的方法，它允许日期和时间组件，并且可以作为数字或字符串进行相同的排序。

根据“Date ISO format”中的数字顺序，转换为本地时区，去掉非数字。例如:

// monkey patch version
Date.prototype.IsoNum = function (n) {
    var tzoffset = this.getTimezoneOffset() * 60000; //offset in milliseconds
    var localISOTime = (new Date(this - tzoffset)).toISOString().slice(0,-1);
    return localISOTime.replace(/[-T:\.Z]/g, '').substring(0,n || 20); // YYYYMMDD
}

使用

var d = new Date();
// Tue Jul 28 2015 15:02:53 GMT+0200 (W. Europe Daylight Time)
console.log(d.IsoNum(8));  // "20150728"
console.log(d.IsoNum(12)); // "201507281502"
console.log(d.IsoNum());   // "20150728150253272"

您可以简单地使用这一行代码来获取日期

var date = new Date().getFullYear() + "-" + (parseInt(new Date().getMonth()) + 1) + "-" + new Date().getDate();

<pre>Date.prototype.getFromFormat = function(format) {
    var yyyy = this.getFullYear().toString();
    format = format.replace(/yyyy/g, yyyy)
    var mm = (this.getMonth()+1).toString(); 
    format = format.replace(/mm/g, (mm[1]?mm:"0"+mm[0]));
    var dd  = this.getDate().toString();
    format = format.replace(/dd/g, (dd[1]?dd:"0"+dd[0]));
    var hh = this.getHours().toString();
    format = format.replace(/hh/g, (hh[1]?hh:"0"+hh[0]));
    var ii = this.getMinutes().toString();
    format = format.replace(/ii/g, (ii[1]?ii:"0"+ii[0]));
    var ss  = this.getSeconds().toString();
    format = format.replace(/ss/g, (ss[1]?ss:"0"+ss[0]));
    var ampm = (hh >= 12) ? "PM" : "AM";
    format = format.replace(/ampm/g, (ampm[1]?ampm:"0"+ampm[0]));
    return format;
};
var time_var = $('#899_TIME');
var myVar = setInterval(myTimer, 1000);
function myTimer() {
    var d = new Date(); 
    var date = d.getFromFormat('dd-mm-yyyy hh:ii:ss:ampm');
    time_var.text(date);

} </pre>

use the code and get the output like **26-07-2017 12:29:34:PM**

check the below link for your reference

https://parthiban037.wordpress.com/2017/07/26/date-and-time-format-in-oracle-apex-using-javascript/ 

[day,,month,,year]= Intl.DateTimeFormat(undefined, { year: 'numeric', month: '2-digit', day: '2-digit' }).formatToParts(new Date()),year.value+month.value+day.value

or

new Date().toJSON().slice(0,10).replace(/\/|-/g,'')