DateTime t1 = Convert.ToDateTime("2012-12-31 23:59:00");
DateTime t2 = Convert.ToDateTime("2013-1-1 00:01:00");
TimeSpan ts = t2 - t1;
int ss = Convert.ToInt32(ts.TotalMinutes);
textBox1.Text = ss.ToString();
原文地址:http://www.cnblogs.com/xiaogongzhu/p/3825579.html