C# 多线程实现查看当前系统时间

 1 using System;
 2 using System.Threading;
 3 using System.Windows.Forms;
 4 
 5 namespace EXP3_C53_GetTime_threading
 6 {
 7     public partial class Form1 : Form
 8     {
 9         public Form1()
10         {
11             InitializeComponent();
12         }
13         bool flag = false;
14 
15         public void showTime()
16         {
17             while (true)
18             {
19                 DateTime dateTime = DateTime.Now;
20                 textBox1.Text = "当前系统时间为：" + dateTime.ToString();
21                 Thread.Sleep(1000);
22             }
23         }
24 
25         private void button1_Click(object sender, EventArgs e)
26         {
27             flag = true;
28             if (flag)
29             {
30                 Thread P_thread = new Thread(new ThreadStart(showTime));
31                 P_thread.IsBackground = true;
32                 P_thread.Start();
33             }
34         }
35 
36     }
37 }