一 基本知识

millisecond 毫秒

microsecond 微秒

nanosecond 纳秒

1秒=1000毫秒 1毫秒=1000微秒 1微秒=1000纳秒

二 perl

perl中可以使用time或localtime来获得时间，time返回从1970年1月1日0点的秒数，localtime返回当前时间的字符串表示，或者年月日等得tuple表示。

#!/usr/bin/perl use strict; use warnings; use POSIX qw(strftime); # seconds from 1970.01.01 00:00:00 my $ti = time(); print $ti; print "n"; print strftime("%Y-%m-%d %H:%M:%Sn", localtime($ti)); #1310623469 #2011-07-14 14:03:58 my $t = localtime(); print $t; print "n"; #Thu Jul 14 12:25:16 2011 my ($sec, $min, $hour, $mday, $mon, $year, $wday, $yday, $isdst)=localtime(); print $year; print "n"; #111 print strftime("%Y-%m-%d %H:%M:%Sn", localtime()); #2011-07-14 12:26:01

三 c#

1tick = 100 nanosecond

using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace MyTest { class Program { static void DateTimeTest() { DateTime dt2 = DateTime.Now; Console.WriteLine(dt2.Ticks); Console.WriteLine(dt2.ToString("MM/dd/yyyy hh:mm:ss")); } static DateTime? ConvertPerlTimeToDateTime(string perltime) { DateTime? dt = null; //perl time variable : seconds from 1970.01.01 00:00:00 string sdt = perltime; long ldt = 0; if (long.TryParse(sdt, out ldt)) { long ldt2 = new DateTime(1970, 1, 1).Ticks + ldt * 1000 * 1000 * 10; dt = new DateTime(ldt2, DateTimeKind.Local); Console.WriteLine(dt.Value.ToString("MM/dd/yyyy hh:mm:ss")); } return dt; } static void Main(string[] args) { DateTimeTest(); ConvertPerlTimeToDateTime("1309423883"); //634462479788396720 //07/14/2011 01:46:18 //06/30/2011 08:51:23 } } }

四 python

python的perl相似，time也是从1970年1月1日开始的秒数。

import time ISOTIMEFORMAT='%Y-%m-%d %X' # seconds from 1970.01.01 00:00:00 t = time.time() print (t) print time.strftime(ISOTIMEFORMAT,time.localtime(t)) #1310623143.12 #2011-07-14 13:59:03 (year,mon,day,hour,min,sec,wday,yday,isdst) = time.localtime() print (year) print (time.strftime(ISOTIMEFORMAT, time.localtime())) #2011 #2011-07-14 13:59:03