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DateTime start = DateTime.Now;   
DateTime end = DateTime.Now;
//C#的日期型態可直接相減並傳回TimeSpan物件
TimeSpan ts = end - start;
 
//時間差換算成秒
String s1 = ts.TotalSeconds.ToString();
//時間差換算成分
String s2 = ts.TotalMinutes.ToString();

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