使用Timer组件实现倒计时

        private void timer1_Tick(object sender, EventArgs e)
        {
            DateTime get_time = DateTime.Now;
            DateTime str_time = DateTime.Parse(dateTimePicker1.Text.Substring(0,19));
            textBox1.Text = get_time.ToString();
            txtyear.Text = DateAndTime.DateDiff(
                "yyyy",get_time,str_time,FirstDayOfWeek.Sunday,FirstWeekOfYear.FirstFourDays).ToString();
            txtmonth.Text = DateAndTime.DateDiff(
                "m", get_time, str_time, FirstDayOfWeek.Sunday, FirstWeekOfYear.FirstFourDays).ToString();
            txtday.Text = DateAndTime.DateDiff(
                "d", get_time, str_time, FirstDayOfWeek.Sunday, FirstWeekOfYear.FirstFourDays).ToString();
            txthour.Text = DateAndTime.DateDiff(
                "h", get_time, str_time, FirstDayOfWeek.Sunday, FirstWeekOfYear.FirstFourDays).ToString();
            txtmintue.Text = DateAndTime.DateDiff(
                "m", get_time, str_time, FirstDayOfWeek.Sunday, FirstWeekOfYear.FirstFourDays).ToString();
            txtsecon.Text = DateAndTime.DateDiff(
                "s", get_time, str_time, FirstDayOfWeek.Sunday, FirstWeekOfYear.FirstFourDays).ToString();
        }