c#时间间隔的计算

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace 时间间隔的计算
{
public partial class Form1 : Form
{
TimeSpan begintime;//开始时间
TimeSpan endtime;//结束时间
TimeSpan ts;//时间间隔

public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{
begintime = new TimeSpan(DateTime.Now.Ticks);
MessageBox.Show(begintime.Hours.ToString() + "时" + begintime.Minutes.ToString() + "分" + begintime.Seconds.ToString() + "秒");
}

private void button2_Click(object sender, EventArgs e)
{
endtime = new TimeSpan(DateTime.Now.Ticks);
MessageBox.Show(endtime.Hours.ToString() + "时" + endtime.Minutes.ToString() + "分" + endtime.Seconds.ToString() + "秒");
}

private void button3_Click(object sender, EventArgs e)
{
if (begintime != null && endtime != null)
{
ts = endtime.Subtract(begintime).Duration();
MessageBox.Show(ts.Hours.ToString() + "小时" + ts.Minutes.ToString() + "分" + ts.Seconds.ToString() + "秒");
}
}
}
}