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

// Calculate total days in current year
int daysInYear;

for (var i = 1; i <= 12; i++)
    daysInYear += DateTime.DaysInMonth(DateTime.Now.Year, i);

// Past date
DateTime dateToCompare = DateTime.Now.Subtract(TimeSpan.FromMinutes(582));

// Calculate difference between current date and past date
double diff = (DateTime.Now - dateToCompare).TotalMilliseconds;

TimeSpan ts = TimeSpan.FromMilliseconds(diff);

var years = ts.TotalDays / daysInYear; // Years
var months = ts.TotalDays / (daysInYear / (double)12); // Months
var weeks = ts.TotalDays / 7; // Weeks
var days = ts.TotalDays; // Days
var hours = ts.TotalHours; // Hours
var minutes = ts.TotalMinutes; // Minutes
var seconds = ts.TotalSeconds; // Seconds

if (years >= 1)
    Console.WriteLine(Math.Round(years, 0) + " year(s) ago");
else if (months >= 1)
    Console.WriteLine(Math.Round(months, 0) + " month(s) ago");
else if (weeks >= 1)
    Console.WriteLine(Math.Round(weeks, 0) + " week(s) ago");
else if (days >= 1)
    Console.WriteLine(Math.Round(days, 0) + " days(s) ago");
else if (hours >= 1)
    Console.WriteLine(Math.Round(hours, 0) + " hour(s) ago");
else if (minutes >= 1)
    Console.WriteLine(Math.Round(minutes, 0) + " minute(s) ago");
else if (seconds >= 1)
    Console.WriteLine(Math.Round(seconds, 0) + " second(s) ago");

Console.ReadLine();

其他回答

// Calculate total days in current year
int daysInYear;

for (var i = 1; i <= 12; i++)
    daysInYear += DateTime.DaysInMonth(DateTime.Now.Year, i);

// Past date
DateTime dateToCompare = DateTime.Now.Subtract(TimeSpan.FromMinutes(582));

// Calculate difference between current date and past date
double diff = (DateTime.Now - dateToCompare).TotalMilliseconds;

TimeSpan ts = TimeSpan.FromMilliseconds(diff);

var years = ts.TotalDays / daysInYear; // Years
var months = ts.TotalDays / (daysInYear / (double)12); // Months
var weeks = ts.TotalDays / 7; // Weeks
var days = ts.TotalDays; // Days
var hours = ts.TotalHours; // Hours
var minutes = ts.TotalMinutes; // Minutes
var seconds = ts.TotalSeconds; // Seconds

if (years >= 1)
    Console.WriteLine(Math.Round(years, 0) + " year(s) ago");
else if (months >= 1)
    Console.WriteLine(Math.Round(months, 0) + " month(s) ago");
else if (weeks >= 1)
    Console.WriteLine(Math.Round(weeks, 0) + " week(s) ago");
else if (days >= 1)
    Console.WriteLine(Math.Round(days, 0) + " days(s) ago");
else if (hours >= 1)
    Console.WriteLine(Math.Round(hours, 0) + " hour(s) ago");
else if (minutes >= 1)
    Console.WriteLine(Math.Round(minutes, 0) + " minute(s) ago");
else if (seconds >= 1)
    Console.WriteLine(Math.Round(seconds, 0) + " second(s) ago");

Console.ReadLine();
var ts = new TimeSpan(DateTime.Now.Ticks - dt.Ticks);

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?

using System;
using System.Collections.Generic;
using System.Linq;

public static class RelativeDateHelper
{
    private static Dictionary<double, Func<double, string>> sm_Dict = null;

    private static Dictionary<double, Func<double, string>> DictionarySetup()
    {
        var dict = new Dictionary<double, Func<double, string>>();
        dict.Add(0.75, (mins) => "less than a minute");
        dict.Add(1.5, (mins) => "about a minute");
        dict.Add(45, (mins) => string.Format("{0} minutes", Math.Round(mins)));
        dict.Add(90, (mins) => "about an hour");
        dict.Add(1440, (mins) => string.Format("about {0} hours", Math.Round(Math.Abs(mins / 60)))); // 60 * 24
        dict.Add(2880, (mins) => "a day"); // 60 * 48
        dict.Add(43200, (mins) => string.Format("{0} days", Math.Floor(Math.Abs(mins / 1440)))); // 60 * 24 * 30
        dict.Add(86400, (mins) => "about a month"); // 60 * 24 * 60
        dict.Add(525600, (mins) => string.Format("{0} months", Math.Floor(Math.Abs(mins / 43200)))); // 60 * 24 * 365 
        dict.Add(1051200, (mins) => "about a year"); // 60 * 24 * 365 * 2
        dict.Add(double.MaxValue, (mins) => string.Format("{0} years", Math.Floor(Math.Abs(mins / 525600))));

        return dict;
    }

    public static string ToRelativeDate(this DateTime input)
    {
        TimeSpan oSpan = DateTime.Now.Subtract(input);
        double TotalMinutes = oSpan.TotalMinutes;
        string Suffix = " ago";

        if (TotalMinutes < 0.0)
        {
            TotalMinutes = Math.Abs(TotalMinutes);
            Suffix = " from now";
        }

        if (null == sm_Dict)
            sm_Dict = DictionarySetup();

        return sm_Dict.First(n => TotalMinutes < n.Key).Value.Invoke(TotalMinutes) + Suffix;
    }
}

与此问题的另一个答案相同,但作为静态字典的扩展方法。

当您知道查看者的时区时,以日为单位使用日历日可能会更清晰。我不熟悉.NET库,所以我不知道如何在C#中实现这一点。

在消费者网站上,你也可以在一分钟内用手洗。“不到一分钟前”或“刚刚”就足够了。