如何在JavaScript中格式化日期？

如果你想要一个简短易懂的函数，可以根据自己的需求进行调整。

timeStamp参数是从1970年开始计算的毫秒数 - 它可以通过new Date().getTime()以及其他许多设备来获取...

好吧，我改变了主意。我增加了一个额外的函数来进行零填充。可恶！

 function zeroPad(aNumber) {
     return ("0"+aNumber).slice(-2);
 }
 function humanTime(timeStamp) {
    var M = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
    var D = new Date(timeStamp); // 23 Aug 2016 16:45:59 <-- Desired format.
    return D.getDate() + " " + M[D.getMonth()] + " " + D.getFullYear() + " " + D.getHours() + ":" + zeroPad(d.getMinutes()) + ":" + zeroPad(D.getSeconds());
 }

 var dtFormat = require('dtformat');
   var today = new Date();
   dtFormat(today, "dddd, mmmm dS, yyyy, h:MM:ss TT");

var now = new Date()
months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
var formattedDate = now.getDate()  + "-" + months[now.getMonth()] + "-" + now.getFullYear()
alert(formattedDate)

简短、广泛兼容的方法：

function formatDate(date) {
    date.toISOString()
    .replace(/^(\d+)-(\d+)-(\d+).*$/, // Only extract Y-M-D
        function (a,y,m,d) {
            return [
                d, // Day
                ['Jan','Feb','Mar','Apr','May','Jun',  // Month Names
                'Jul','Ago','Sep','Oct','Nov','Dec']
                [m-1], // Month
                y  // Year
            ].join('-') // Stitch together
        })
}

date.toISOString().replace(/^(\d+)-(\d+)-(\d+)T(\d+):(\d+):(\d+).(\d+)Z$/, function (a,y,m,d) {return [d,['Jan','Feb','Mar','Apr','May','Jun','Jul','Ago','Sep','Oct','Nov','Dic'][m-1],y].join('-')})

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

"11-Nov-2015"

您可以使用其他方式格式化日期：

function formatDate(dDate,sMode){
    var today = dDate;
    var dd = today.getDate();
    var mm = today.getMonth()+1; //January is 0!
    var yyyy = today.getFullYear();
    if(dd<10) {
        dd = '0'+dd
    }
    if(mm<10) {
        mm = '0'+mm
    }
    if (sMode+""==""){
        sMode = "dd/mm/yyyy";
    }
    if (sMode == "yyyy-mm-dd"){
        return  yyyy + "-" + mm + "-" + dd + "";
    }
    if (sMode == "dd/mm/yyyy"){
        return  dd + "/" + mm + "/" + yyyy;
    }
}

new Date('2015-1-1').to('dd.MM.yy')         // Outputs 01.01.2015
"2015-01-01T10:11:12.123Z".to('dd.MM.yy')   // Outputs 01.01.2015

本地化文件（smarti.to.{culture}.js）中还定义了自定义短模式。例如（smarti.to.et-EE.js）：

new Date('2015-1-1').to('d')                // Outputs 1.01.2015

同时，它还具备多种格式化能力：

smarti.format('{0:n2} + {1:n2} = {2:n2}', 1, 2, 3)   // Output: 1,00 + 2,00 = 3,00

yy = 两位数年份; yyyy = 完整的年份

M = 数字月份; MM = 两位数字月份; MMM = 简写月份名称; MMMM = 完整的月份名称

EEEE = 完整的星期几名称; EEE = 简写星期几名称

d = 数字日期; dd = 两位数字日期

h = 小时; hh = 两位数字小时

m = 分钟; mm = 两位数字分钟

s = 秒; ss = 两位数字秒

S = 毫秒

与SimpleDateFormat类（Java）使用相似的格式化形式。

var monthNames = [
  "January", "February", "March", "April", "May", "June", "July",
  "August", "September", "October", "November", "December"
];
var dayOfWeekNames = [
  "Sunday", "Monday", "Tuesday",
  "Wednesday", "Thursday", "Friday", "Saturday"
];
function formatDate(date, formatStr){
    if (!formatStr) {
      formatStr = 'dd/mm/yyyy';
    }
    var day = date.getDate(),
        month = date.getMonth(),
        year = date.getFullYear(),
        hour = date.getHours(),
        minute = date.getMinutes(),
        second = date.getSeconds(),
        miliseconds = date.getMilliseconds(),
        hh = twoDigitPad(hour),
        mm = twoDigitPad(minute),
        ss = twoDigitPad(second),
        EEEE = dayOfWeekNames[date.getDay()],
        EEE = EEEE.substr(0, 3),
        dd = twoDigitPad(day),
        M = month + 1,
        MM = twoDigitPad(M),
        MMMM = monthNames[month],
        MMM = MMMM.substr(0, 3),
        yyyy = year + "",
        yy = yyyy.substr(2, 2)
    ;
    return formatStr
      .replace('hh', hh).replace('h', hour)
      .replace('mm', mm).replace('m', minute)
      .replace('ss', ss).replace('s', second)
      .replace('S', miliseconds)
      .replace('dd', dd).replace('d', day)
      .replace('MMMM', MMMM).replace('MMM', MMM).replace('MM', MM).replace('M', M)
      .replace('EEEE', EEEE).replace('EEE', EEE)
      .replace('yyyy', yyyy)
      .replace('yy', yy)
    ;
}
function twoDigitPad(num) {
    return num < 10 ? "0" + num : num;
}
console.log(formatDate(new Date()));
console.log(formatDate(new Date(), 'EEEE, MMMM d, yyyy hh:mm:ss:S'));
console.log(formatDate(new Date(), 'EEE, MMM d, yyyy hh:mm'));
console.log(formatDate(new Date(), 'yyyy-MM-dd hh:mm:ss:S'));
console.log(formatDate(new Date(), 'yy-MM-dd hh:mm'));

在我的案例中，我已经将日期格式从'01/07/2022'转换为'2022-07-01'

const formatDate = date => {
const d = new Date(date)
let month = (d.getMonth() + 1).toString()
let day = d.getDate().toString()
const year = d.getFullYear()
if (month.length < 2) {
    month = '0' + month
}
if (day.length < 2) {
    day = '0' + day
}
return [ year, month, day ].join('-')
}

console.log(formatDate('01/07/2022'))

使用此过程

const MONTHS = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sept', 'Oct', 'Nov', 'Dec']

const date = new Date()

const dateString = `${date.getDate()}-${MONTHS[date.getMonth()]}-${date.getFullYear()}`

console.log(dateString)

这是主要答案的修改版本，将月份改为3个字符，年份改为2位数字：

function formatDate(date) {
    var monthNames = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];
    var day = date.getDate(), monthIndex = date.getMonth(), year = date.getFullYear().toString().substr(-2);
    return day + ' ' + monthNames[monthIndex] + ' ' + year;
}

document.write(formatDate(new Date()));