这应该正确地处理任何有效的时间戳，包括Date.now()、单数单位和未来日期。我漏掉了月份，但是这些月份应该很容易加进去。我尽量保持它的可读性。

function getTimeInterval(date) { let seconds = Math.floor((Date.now() - date) / 1000); let unit = "second"; let direction = "ago"; if (seconds < 0) { seconds = -seconds; direction = "from now"; } let value = seconds; if (seconds >= 31536000) { value = Math.floor(seconds / 31536000); unit = "year"; } else if (seconds >= 86400) { value = Math.floor(seconds / 86400); unit = "day"; } else if (seconds >= 3600) { value = Math.floor(seconds / 3600); unit = "hour"; } else if (seconds >= 60) { value = Math.floor(seconds / 60); unit = "minute"; } if (value != 1) unit = unit + "s"; return value + " " + unit + " " + direction; } console.log(getTimeInterval(Date.now())); // 0 seconds ago console.log(getTimeInterval(Date.now() + 1000)); // 1 second from now console.log(getTimeInterval(Date.now() - 1000)); // 1 second ago console.log(getTimeInterval(Date.now() + 60000)); // 1 minute from now console.log(getTimeInterval(Date.now() - 120000)); // 2 minutes ago console.log(getTimeInterval(Date.now() + 120000)); // 2 minutes from now console.log(getTimeInterval(Date.now() + 3600000)); // 1 hour from now console.log(getTimeInterval(Date.now() + 360000000000)); // 11 years from now console.log(getTimeInterval(0)); // 49 years ago

const createdAt = moment(created_at).fromNow()

量身定制的解决方案

        const duration = moment.duration(moment().diff(moment(created_at)))
        const createdAt = duration.as('week') >= 1
          ? `${Math.floor(duration.as('week'))} week(s)`
          : duration.as('day') >= 1
            ? `${Math.floor(duration.as('day'))} day(s)`
            : duration.as('hour') >= 1
              ? `${Math.floor(duration.as('hour'))} hour(s)`
              : `${Math.floor(duration.as('minute'))} minute(s)`

function timeago(date) {
    var seconds = Math.floor((new Date() - date) / 1000);
    if(Math.round(seconds/(60*60*24*365.25)) >= 2) return Math.round(seconds/(60*60*24*365.25)) + " years ago";
    else if(Math.round(seconds/(60*60*24*365.25)) >= 1) return "1 year ago";
    else if(Math.round(seconds/(60*60*24*30.4)) >= 2) return Math.round(seconds/(60*60*24*30.4)) + " months ago";
    else if(Math.round(seconds/(60*60*24*30.4)) >= 1) return "1 month ago";
    else if(Math.round(seconds/(60*60*24*7)) >= 2) return Math.round(seconds/(60*60*24*7)) + " weeks ago";
    else if(Math.round(seconds/(60*60*24*7)) >= 1) return "1 week ago";
    else if(Math.round(seconds/(60*60*24)) >= 2) return Math.round(seconds/(60*60*24)) + " days ago";
    else if(Math.round(seconds/(60*60*24)) >= 1) return "1 day ago";
    else if(Math.round(seconds/(60*60)) >= 2) return Math.round(seconds/(60*60)) + " hours ago";
    else if(Math.round(seconds/(60*60)) >= 1) return "1 hour ago";
    else if(Math.round(seconds/60) >= 2) return Math.round(seconds/60) + " minutes ago";
    else if(Math.round(seconds/60) >= 1) return "1 minute ago";
    else if(seconds >= 2)return seconds + " seconds ago";
    else return seconds + "1 second ago";
}

简单易读版本:

const relativeTimePeriods = [
    [31536000, 'year'],
    [2419200, 'month'],
    [604800, 'week'],
    [86400, 'day'],
    [3600, 'hour'],
    [60, 'minute'],
    [1, 'second']
];

function relativeTime(date, isUtc=true) {
    if (!(date instanceof Date)) date = new Date(date * 1000);
    const seconds = (new Date() - date) / 1000;
    for (let [secondsPer, name] of relativeTimePeriods) {
        if (seconds >= secondsPer) {
            const amount = Math.floor(seconds / secondsPer);
            return `${amount} ${name}${amount ? 's' : ''}s ago`;
        }
    }
    return 'Just now';
}

function timeSince(date) { var seconds = Math.floor((new Date() - date) / 1000); var interval = seconds / 31536000; if (interval > 1) { return Math.floor(interval) + " years"; } interval = seconds / 2592000; if (interval > 1) { return Math.floor(interval) + " months"; } interval = seconds / 86400; if (interval > 1) { return Math.floor(interval) + " days"; } interval = seconds / 3600; if (interval > 1) { return Math.floor(interval) + " hours"; } interval = seconds / 60; if (interval > 1) { return Math.floor(interval) + " minutes"; } return Math.floor(seconds) + " seconds"; } var aDay = 24*60*60*1000; console.log(timeSince(new Date(Date.now()-aDay))); console.log(timeSince(new Date(Date.now()-aDay*2)));

我还没有检查(虽然这并不难)，但我认为Stack Exchange站点使用jquery。Timeago插件来创建这些时间字符串。

这个插件使用起来很简单，而且很干净，还能自动更新。

下面是一个简单的例子(来自插件的主页):

First, load jQuery and the plugin: <script src="jquery.min.js" type="text/javascript"></script> <script src="jquery.timeago.js" type="text/javascript"></script> Now, let's attach it to your timestamps on DOM ready: jQuery(document).ready(function() { jQuery("abbr.timeago").timeago(); }); This will turn all abbr elements with a class of timeago and an ISO 8601 timestamp in the title: <abbr class="timeago" title="2008-07-17T09:24:17Z">July 17, 2008</abbr> into something like this: <abbr class="timeago" title="July 17, 2008">about a year ago</abbr> which yields: about a year ago. As time passes, the timestamps will automatically update.