如果你有两个unix时间戳，你可以使用这个函数(为了清晰起见，写得更详细一点):

// Calculate number of days between two unix timestamps
// ------------------------------------------------------------
var daysBetween = function(timeStampA, timeStampB) {
    var oneDay = 24 * 60 * 60 * 1000; // hours * minutes * seconds * milliseconds
    var firstDate = new Date(timeStampA * 1000);
    var secondDate = new Date(timeStampB * 1000);
    var diffDays = Math.round(Math.abs((firstDate.getTime() - secondDate.getTime())/(oneDay)));
    return diffDays;
};

例子:

daysBetween(1096580303, 1308713220); // 2455

使用Moment.js

Var future = moment('05/02/2015'); Var start = moment('04/23/2015'); Var d =未来。diff(开始,“天”);/ / 9 console.log (d); < script src = " https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.17.1/moment-with-locales.min.js " > < /脚本>

更好的解决方案

忽略时间部分

如果两个日期相同，则返回0。

function dayDiff(firstDate, secondDate) { firstDate = new Date(firstDate); secondDate = new Date(secondDate); if (!isNaN(firstDate) && !isNaN(secondDate)) { firstDate.setHours(0, 0, 0, 0); //ignore time part secondDate.setHours(0, 0, 0, 0); //ignore time part var dayDiff = secondDate - firstDate; dayDiff = dayDiff / 86400000; // divide by milisec in one day console.log(dayDiff); } else { console.log("Enter valid date."); } } $(document).ready(function() { $('input[type=datetime]').datepicker({ dateFormat: "mm/dd/yy", changeMonth: true, changeYear: true }); $("#button").click(function() { dayDiff($('#first').val(), $('#second').val()); }); }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css"> <script src="//code.jquery.com/ui/1.12.1/jquery-ui.js"></script> <input type="datetime" id="first" value="12/28/2016" /> <input type="datetime" id="second" value="12/28/2017" /> <input type="button" id="button" value="Calculate">

当我想在两个日期上做一些计算时，我发现了这个问题，但是日期有小时和分钟的值，我修改了@michael-liu的答案来满足我的要求，它通过了我的测试。

差异日期2012-12-31 23:00和2013-01-01 01:00应该等于1。(2小时) 差异日期2012-12-31 01:00和2013-01-01 23:00应该等于1。(46个小时)

function treatAsUTC(date) {
    var result = new Date(date);
    result.setMinutes(result.getMinutes() - result.getTimezoneOffset());
    return result;
}

var millisecondsPerDay = 24 * 60 * 60 * 1000;
function diffDays(startDate, endDate) {
    return Math.floor(treatAsUTC(endDate) / millisecondsPerDay) - Math.floor(treatAsUTC(startDate) / millisecondsPerDay);
}

在这种情况下使用moment会容易得多，你可以试试这个:

    let days = moment(yourFirstDateString).diff(moment(yourSecondDateString), 'days');

它会给你一个整数值，比如1、2、5、0等，所以你可以很容易地使用条件检查，比如:

if(days < 1) {

此外，还有一件事是你可以得到更准确的时间差结果(以小数形式，如1.2,1.5,0.7等)，使用以下语法得到这种结果:

let days = moment(yourFirstDateString).diff(moment(yourSecondDateString), 'days', true);

如果你有任何进一步的疑问，请告诉我

1970-01-01之前和2038-01-19之后的贡献

function DateDiff(aDate1, aDate2) {
  let dDay = 0;
  this.isBissexto = (aYear) => {
    return (aYear % 4 == 0 && aYear % 100 != 0) || (aYear % 400 == 0);
  };
  this.getDayOfYear = (aDate) => {
    let count = 0;
    for (let m = 0; m < aDate.getUTCMonth(); m++) {
      count += m == 1 ? this.isBissexto(aDate.getUTCFullYear()) ? 29 : 28 : /(3|5|8|10)/.test(m) ? 30 : 31;
    }
    count += aDate.getUTCDate();
    return count;
  };
  this.toDays = () => {
    return dDay;
  };
  (() => {
    let startDate = aDate1.getTime() <= aDate2.getTime() ? new Date(aDate1.toISOString()) : new Date(aDate2.toISOString());
    let endDate = aDate1.getTime() <= aDate2.getTime() ? new Date(aDate2.toISOString()) : new Date(aDate1.toISOString());
    while (startDate.getUTCFullYear() != endDate.getUTCFullYear()) {
      dDay += (this.isBissexto(startDate.getFullYear())? 366 : 365) - this.getDayOfYear(startDate) + 1;
      startDate = new Date(startDate.getUTCFullYear()+1, 0, 1);
    }
    dDay += this.getDayOfYear(endDate) - this.getDayOfYear(startDate);
  })();
}