这是我实现npm插件的方式

var monthNames = [
  "January", "February", "March",
  "April", "May", "June", "July",
  "August", "September", "October",
  "November", "December"
];

var Days = [
  "Sunday", "Monday", "Tuesday", "Wednesday",
  "Thursday", "Friday", "Saturday"
];

var formatDate = function(dt,format){
  format = format.replace('ss', pad(dt.getSeconds(),2));
  format = format.replace('s', dt.getSeconds());
  format = format.replace('dd', pad(dt.getDate(),2));
  format = format.replace('d', dt.getDate());
  format = format.replace('mm', pad(dt.getMinutes(),2));
  format = format.replace('m', dt.getMinutes());
  format = format.replace('MMMM', monthNames[dt.getMonth()]);
  format = format.replace('MMM', monthNames[dt.getMonth()].substring(0,3));
  format = format.replace('MM', pad(dt.getMonth()+1,2));
  format = format.replace(/M(?![ao])/, dt.getMonth()+1);
  format = format.replace('DD', Days[dt.getDay()]);
  format = format.replace(/D(?!e)/, Days[dt.getDay()].substring(0,3));
  format = format.replace('yyyy', dt.getFullYear());
  format = format.replace('YYYY', dt.getFullYear());
  format = format.replace('yy', (dt.getFullYear()+"").substring(2));
  format = format.replace('YY', (dt.getFullYear()+"").substring(2));
  format = format.replace('HH', pad(dt.getHours(),2));
  format = format.replace('H', dt.getHours());
  return format;
}

pad = function(n, width, z) {
  z = z || '0';
  n = n + '';
  return n.length >= width ? n : new Array(width - n.length + 1).join(z) + n;
}

@Sébastien——可选的所有浏览器支持

new Date(parseInt(496407600)*1000).toLocaleDateString('de-DE', {
year: 'numeric',
month: '2-digit',
day: '2-digit'
}).replace(/\./g, '/');

文档：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleDateString

基于Date.toLocaleDateString的高阶标记模板文本示例：

const date = new Date(Date.UTC(2020, 4, 2, 3, 23, 16, 738));
const fmt = (dt, lc = "en-US") => (str, ...expr) =>
    str.map((str, i) => str + (expr[i]?dt.toLocaleDateString(lc, expr[i]) :'')).join('')

console.log(fmt(date)`${{year: 'numeric'}}-${{month: '2-digit'}}-${{day: '2-digit'}}`);
// expected output: "2020-05-02"

如果您已经在项目中使用ExtJS，则可以使用Ext.Date:

var date = new Date();
Ext.Date.format(date, "d-M-Y");

返回：

"11-Nov-2015"

使用date.format库：

var dateFormat = require('dateformat');
var now = new Date();
dateFormat(now, "dddd, mmmm dS, yyyy, h:MM:ss TT");

返回：

Saturday, June 9th, 2007, 5:46:21 PM 

npm上的日期格式

http://jsfiddle.net/phZr7/1/

var today = new Date();
var formattedToday = today.toLocaleDateString() + ' ' + today.toLocaleTimeString();

Sugar.js对Date对象有很好的扩展，包括Date.format方法。

文档中的示例：

Date.create().format('{Weekday} {Month} {dd}, {yyyy}');

Date.create().format('{12hr}:{mm}{tt}')