1  static void Main()

 2         {

 3             if (Process.GetProcessesByName(Process.GetCurrentProcess().ProcessName).Length > 1)

 4             {

 5                 MessageBox.Show("程序已经运行了一个实例，该程序只允许有一个实例");

 6                 Application.Exit();

 7                 return;

 8             }

 9             bool createNew;

10             using (System.Threading.Mutex mutex = new System.Threading.Mutex(true, Application.ProductName, out createNew))

11             {

12                 if (!createNew)

13                 {

14                     MessageBox.Show("应用程序已经在运行中...");

15                     System.Threading.Thread.Sleep(1000);

16                     System.Environment.Exit(1);

17                     Application.Exit();

18                 }

19             }

20

21             Application.EnableVisualStyles();

22             Application.SetCompatibleTextRenderingDefault(false);

23             Application.Run(new MainForm());

24         }