多线程之间变量锁的实现

 1 public partial class Form1 : Form
 2     {
 3         string a = "";
 4         static object locker = new object();
 5         public Form1()
 6         {
 7             InitializeComponent();
 8         }
 9 
10         private void button1_Click(object sender, EventArgs e)
11         {
12             Thread a1 = new Thread(new ThreadStart(change1));
13             a1.IsBackground = true;
14             Thread a2 = new Thread(new ThreadStart(change2));
15             a2.IsBackground = true;
16             a1.Start();
17             a2.Start();
18         }
19         private void change1()
20         {
21             lock (locker)
22             {
23                 a = "1";
24                 Thread.Sleep(5000);
25                 MessageBox.Show(a);
26             }
27         }
28         private void change2()
29         {
30             lock (locker)
31             {
32                 a = "2";
33                 MessageBox.Show(a);
34             }
35         }
36     }