给定特定的DateTime值,如何显示相对时间,例如:

2小时前3天前一个月前


当前回答

聚会晚了几年,但我有一个要求,无论是过去还是将来的约会,都要这样做,所以我把杰夫和文森特的约会结合在一起。这是一场盛大的盛会!:)

public static class DateTimeHelper
    {
        private const int SECOND = 1;
        private const int MINUTE = 60 * SECOND;
        private const int HOUR = 60 * MINUTE;
        private const int DAY = 24 * HOUR;
        private const int MONTH = 30 * DAY;

        /// <summary>
        /// Returns a friendly version of the provided DateTime, relative to now. E.g.: "2 days ago", or "in 6 months".
        /// </summary>
        /// <param name="dateTime">The DateTime to compare to Now</param>
        /// <returns>A friendly string</returns>
        public static string GetFriendlyRelativeTime(DateTime dateTime)
        {
            if (DateTime.UtcNow.Ticks == dateTime.Ticks)
            {
                return "Right now!";
            }

            bool isFuture = (DateTime.UtcNow.Ticks < dateTime.Ticks);
            var ts = DateTime.UtcNow.Ticks < dateTime.Ticks ? new TimeSpan(dateTime.Ticks - DateTime.UtcNow.Ticks) : new TimeSpan(DateTime.UtcNow.Ticks - dateTime.Ticks);

            double delta = ts.TotalSeconds;

            if (delta < 1 * MINUTE)
            {
                return isFuture ? "in " + (ts.Seconds == 1 ? "one second" : ts.Seconds + " seconds") : ts.Seconds == 1 ? "one second ago" : ts.Seconds + " seconds ago";
            }
            if (delta < 2 * MINUTE)
            {
                return isFuture ? "in a minute" : "a minute ago";
            }
            if (delta < 45 * MINUTE)
            {
                return isFuture ? "in " + ts.Minutes + " minutes" : ts.Minutes + " minutes ago";
            }
            if (delta < 90 * MINUTE)
            {
                return isFuture ? "in an hour" : "an hour ago";
            }
            if (delta < 24 * HOUR)
            {
                return isFuture ? "in " + ts.Hours + " hours" : ts.Hours + " hours ago";
            }
            if (delta < 48 * HOUR)
            {
                return isFuture ? "tomorrow" : "yesterday";
            }
            if (delta < 30 * DAY)
            {
                return isFuture ? "in " + ts.Days + " days" : ts.Days + " days ago";
            }
            if (delta < 12 * MONTH)
            {
                int months = Convert.ToInt32(Math.Floor((double)ts.Days / 30));
                return isFuture ? "in " + (months <= 1 ? "one month" : months + " months") : months <= 1 ? "one month ago" : months + " months ago";
            }
            else
            {
                int years = Convert.ToInt32(Math.Floor((double)ts.Days / 365));
                return isFuture ? "in " + (years <= 1 ? "one year" : years + " years") : years <= 1 ? "one year ago" : years + " years ago";
            }
        }
    }

其他回答

如果您想获得类似“2天4小时12分钟前”的输出,则需要一个时间跨度:

TimeSpan timeDiff = DateTime.Now-CreatedDate;

然后您可以访问您喜欢的值:

timeDiff.Days
timeDiff.Hours

我是这样做的

var ts = new TimeSpan(DateTime.UtcNow.Ticks - dt.Ticks);
double delta = Math.Abs(ts.TotalSeconds);

if (delta < 60)
{
  return ts.Seconds == 1 ? "one second ago" : ts.Seconds + " seconds ago";
}
if (delta < 60 * 2)
{
  return "a minute ago";
}
if (delta < 45 * 60)
{
  return ts.Minutes + " minutes ago";
}
if (delta < 90 * 60)
{
  return "an hour ago";
}
if (delta < 24 * 60 * 60)
{
  return ts.Hours + " hours ago";
}
if (delta < 48 * 60 * 60)
{
  return "yesterday";
}
if (delta < 30 * 24 * 60 * 60)
{
  return ts.Days + " days ago";
}
if (delta < 12 * 30 * 24 * 60 * 60)
{
  int months = Convert.ToInt32(Math.Floor((double)ts.Days / 30));
  return months <= 1 ? "one month ago" : months + " months ago";
}
int years = Convert.ToInt32(Math.Floor((double)ts.Days / 365));
return years <= 1 ? "one year ago" : years + " years ago";

建议?评论?如何改进此算法?

Nuget上还有一个名为Humanizr的软件包,它实际上运行得很好,并且在.NET Foundation中。

DateTime.UtcNow.AddHours(-30).Humanize() => "yesterday"
DateTime.UtcNow.AddHours(-2).Humanize() => "2 hours ago"

DateTime.UtcNow.AddHours(30).Humanize() => "tomorrow"
DateTime.UtcNow.AddHours(2).Humanize() => "2 hours from now"

TimeSpan.FromMilliseconds(1299630020).Humanize() => "2 weeks"
TimeSpan.FromMilliseconds(1299630020).Humanize(3) => "2 weeks, 1 day, 1 hour"

Scott Hanselman在他的博客上写了一篇文章

我也建议在客户端进行计算。服务器工作更少。

以下是我使用的版本(来自Zach Leatherman)

/*
 * Javascript Humane Dates
 * Copyright (c) 2008 Dean Landolt (deanlandolt.com)
 * Re-write by Zach Leatherman (zachleat.com)
 * 
 * Adopted from the John Resig's pretty.js
 * at http://ejohn.org/blog/javascript-pretty-date
 * and henrah's proposed modification 
 * at http://ejohn.org/blog/javascript-pretty-date/#comment-297458
 * 
 * Licensed under the MIT license.
 */

function humane_date(date_str){
        var time_formats = [
                [60, 'just now'],
                [90, '1 minute'], // 60*1.5
                [3600, 'minutes', 60], // 60*60, 60
                [5400, '1 hour'], // 60*60*1.5
                [86400, 'hours', 3600], // 60*60*24, 60*60
                [129600, '1 day'], // 60*60*24*1.5
                [604800, 'days', 86400], // 60*60*24*7, 60*60*24
                [907200, '1 week'], // 60*60*24*7*1.5
                [2628000, 'weeks', 604800], // 60*60*24*(365/12), 60*60*24*7
                [3942000, '1 month'], // 60*60*24*(365/12)*1.5
                [31536000, 'months', 2628000], // 60*60*24*365, 60*60*24*(365/12)
                [47304000, '1 year'], // 60*60*24*365*1.5
                [3153600000, 'years', 31536000], // 60*60*24*365*100, 60*60*24*365
                [4730400000, '1 century'] // 60*60*24*365*100*1.5
        ];

        var time = ('' + date_str).replace(/-/g,"/").replace(/[TZ]/g," "),
                dt = new Date,
                seconds = ((dt - new Date(time) + (dt.getTimezoneOffset() * 60000)) / 1000),
                token = ' ago',
                i = 0,
                format;

        if (seconds < 0) {
                seconds = Math.abs(seconds);
                token = '';
        }

        while (format = time_formats[i++]) {
                if (seconds < format[0]) {
                        if (format.length == 2) {
                                return format[1] + (i > 1 ? token : ''); // Conditional so we don't return Just Now Ago
                        } else {
                                return Math.round(seconds / format[2]) + ' ' + format[1] + (i > 1 ? token : '');
                        }
                }
        }

        // overflow for centuries
        if(seconds > 4730400000)
                return Math.round(seconds / 4730400000) + ' centuries' + token;

        return date_str;
};

if(typeof jQuery != 'undefined') {
        jQuery.fn.humane_dates = function(){
                return this.each(function(){
                        var date = humane_date(this.title);
                        if(date && jQuery(this).text() != date) // don't modify the dom if we don't have to
                                jQuery(this).text(date);
                });
        };
}

在Java中有没有一种简单的方法可以做到这一点?java.util.Date类似乎相当有限。

下面是我的快速而肮脏的Java解决方案:

import java.util.Date;
import javax.management.timer.Timer;

String getRelativeDate(Date date) {     
  long delta = new Date().getTime() - date.getTime();
  if (delta < 1L * Timer.ONE_MINUTE) {
    return toSeconds(delta) == 1 ? "one second ago" : toSeconds(delta) + " seconds ago";
  }
  if (delta < 2L * Timer.ONE_MINUTE) {
    return "a minute ago";
  }
  if (delta < 45L * Timer.ONE_MINUTE) {
    return toMinutes(delta) + " minutes ago";
  }
  if (delta < 90L * Timer.ONE_MINUTE) {
    return "an hour ago";
  }
  if (delta < 24L * Timer.ONE_HOUR) {
    return toHours(delta) + " hours ago";
  }
  if (delta < 48L * Timer.ONE_HOUR) {
    return "yesterday";
  }
  if (delta < 30L * Timer.ONE_DAY) {
    return toDays(delta) + " days ago";
  }
  if (delta < 12L * 4L * Timer.ONE_WEEK) { // a month
    long months = toMonths(delta); 
    return months <= 1 ? "one month ago" : months + " months ago";
  }
  else {
    long years = toYears(delta);
    return years <= 1 ? "one year ago" : years + " years ago";
  }
}

private long toSeconds(long date) {
  return date / 1000L;
}

private long toMinutes(long date) {
  return toSeconds(date) / 60L;
}

private long toHours(long date) {
  return toMinutes(date) / 60L;
}

private long toDays(long date) {
  return toHours(date) / 24L;
}

private long toMonths(long date) {
  return toDays(date) / 30L;
}

private long toYears(long date) {
  return toMonths(date) / 365L;
}