一. DateTime
在C#中,系統提供了許多關于時間處理的函數,我們可以通過System.DateTime.Now擷取系統時間.當然也可以用DateTime類來建立時間對象.下面給了幾個例子擷取系統時間的方法.
DateTime dt1 = new DateTime(2004, 10, 19); Console.WriteLine("dt1: {0}", dt1); DateTime dt2 = new DateTime(2004, 10, 19, 22, 47, 35); Console.WriteLine("dt2: {0}", dt2); DateTime dt3 = new DateTime(2004, 10, 19, 22, 47, 35, 259); Console.WriteLine("dt3: {0}", dt3); Stringtime1= System.DateTime.Now.ToString("yyyy-MM-dd-hh-mm-ss"); Console.WriteLine(time1); | 程式運作的結果截圖是 dt1:2011-08-13 0:00:00 dt2:2011-08-13 15:49:21 dt3:2011-08-13 15:49:21 2011-08-13-15-49-50 |
System.DateTime.Now.ToString("yyyy-MM-dd-hh-mm-ss")的意思是擷取系統目前時間,并以年-月-日-時-分-秒的格式顯示出來.
再看下一個有管時間的類:Timespan,就字面的意思應該知道它的中文意思時間間隔.先看一個例子:
TimeSpan oneweek = new TimeSpan(4, 12, 0, 0) + new TimeSpan(2, 12, 0, 0); //(4, 12, 0, 0)中的參數分别表示 days,hours,minutes,seconds. DateTime now = DateTime.Now; DateTime past = now - oneweek; Console.WriteLine(oneweek.ToString()); Console.WriteLine(now.ToString()); Console.WriteLine(past.ToString()); | 輸出結果時 15.00:00:00 2011-08-13 16:05:10 2011-08-13 16:05:15 |
.在目前的時間上加上X秒./分/時/天等操作.
DateTime time1 = DateTime.Now; DateTime time2 = DateTime.Now.AddYears(10); DateTime time3 = DateTime.Now.AddMonths(11); DateTime time4 = DateTime.Now.AddDays(7); DateTime time5 = DateTime.Now.AddHours(12); Console.WriteLine(time1.ToString()); Console.WriteLine(time2.ToString()); Console.WriteLine(time3.ToString()); Console.WriteLine(time4.ToString()); Console.WriteLine(time5.ToString()); | 程式運作的結果截圖是: 2011-08-13 16:05:10 2021-08-13 16:05:10 2012-07-13 16:05:10 2011-08-21 16:05:10 2011-08-14 02:05:10 |
DateTime time2 = DateTime.Now.AddYears(10)的意思是把目前時間上加上10年後再指派給 time2;
有關本地時間和标準UTC時間: UTC時間也就是格林威治标準時間.
DateTime local=DateTime.Now;//本地時間 Console.WriteLine("{0},{1},{2}",local.ToString(),local.Kind.ToString(),TimeZone.CurrentTimeZone.StandardName); DateTime utctime=DateTime.UtcNow;//協調通用時間; Console.WriteLine("{0},{1}",utctime.ToString(),utctime.Kind.ToString()); |
2011-08-13 16:05:10,local,中國标準時間
2011-08-13 16:05:10,Utc
二.有關時間格式的問題
時間顯示的格式可以是24或者12小時制的,還有其他方式的.
DateTime local=DateTime.Now;//本地時間 Console.WriteLine("the time is{0: hh:mm tt}",local); Console.WriteLine("Date is {0:ddd MMM dd, yyyy}", local); Console.WriteLine("{0:ddd MMM dd,yyyy}",local); Console.WriteLine("{0: HH :mm :ss tt}",local); Console.WriteLine("{0 :m}",local); | the time is 16:08 AM Date is 六 八月 13,2011 六 八月 13,2011 8月13日 |
TimeSpan在有關時間處理的過程有很多的作用,例如計算兩個時間段之間的時間有多久,或者1個月後的今天是幾号等.
TimeSpan的構造函數有:
TimeSpan oneweek = new TimeSpan(4, 12, 0, 0) + new TimeSpan(2, 12, 0, 0);
那麼oneweek就等于7天:4.5天加2.5天
TimeSpan tp = new TimeSpan(1,50,20,10);//dd hh mm ss
TimeSpan tp2 = new TimeSpan(1, 50, 20);// hh mm ss
TimeSpan tp3 = new TimeSpan(1,1,1,1,1);//dd hh mm ss msms
//(4, 12, 0, 0)中的參數分别表示days,hours,minutes,seconds.
同時我們可以用TimeSpan的靜态方法來給TimeSpan的執行個體對象指派
請看下面的例子:
TimeSpan spa1 = TimeSpan.FromDays(10); TimeSpan spa2 = TimeSpan.FromHours(10); TimeSpan spa3 = TimeSpan.FromMinutes(44); TimeSpan spa4 = TimeSpan.FromSeconds(5); TimeSpan spa5 = TimeSpan.FromMilliseconds(55); TimeSpan spa6 = TimeSpan.FromTicks(200);//時間的刻度 Console.WriteLine(spa1); Console.WriteLine(spa2); Console.WriteLine(spa3); Console.WriteLine(spa4); Console.WriteLine(spa5); Console.WriteLine(spa6); | 輸出結果是: 10.00:00:00 10:00:00 00:44:00 00:00:05 00:00:00.0550000 00:00:00.0000200 |