C# 防止WinForm重复运行

   1: using System;

   2: using System.Collections.Generic;

   3: using System.Windows.Forms;

   4: using System.Diagnostics;

   5:  

   6: namespace TestProcessCount

   7: {

   8: static class Program

   9:     {

  10: /// <summary>

  11: /// The main entry point for the application.

  12: /// </summary>

  13:         [STAThread]

  14: static void Main()

  15:         {

  16: int processCount = 0;

  17:             Process[] pa = Process.GetProcesses();//获取当前进程数组。

  18: foreach (Process PTest in pa)

  19:               {

  20: if (PTest.ProcessName == Process.GetCurrentProcess().ProcessName)

  21:                 {

  22:                     processCount += 1;

  23:                 }

  24:             }

  25:  

  26: if (processCount > 1)

  27:             {

  28:                 DialogResult dr;

  29:                 dr = MessageBox.Show( Process.GetCurrentProcess().ProcessName+"程序已经在运行！", "退出程序", MessageBoxButtons.OK, MessageBoxIcon.Error);

  30: return;   

  31:             }

  32:             Application.EnableVisualStyles();

  33:             Application.SetCompatibleTextRenderingDefault(false);

  34:             Application.Run(new frmBrowser());

  35:         }

  36:     }

  37: }

  38:  

   1: static class Program

   2: {

   3: // Uses to active the exist window

   4:     [DllImport("User32.dll")]

   5: public static extern void SetForegroundWindow(IntPtr hwnd);

   6:     [DllImport("User32.dll")]

   7: private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);

   8: // HIDE=0, NORMAL=1, MINIMIZED=2, MAXIMIZED=3, NOACTIVATE = 4;   

   9: private const int WS_SHOWSTYLE = 1;

  10:  

  11: /// <summary>

  12: /// The main entry point for the application.

  13: /// </summary>

  14:     [STAThread]

  15: static void Main()

  16:     {

  17: bool createdNew; 

  18:         Mutex mutex = new Mutex(true, Application.ProductName, out createdNew);

  19: if (createdNew)

  20:         {

  21:             Application.EnableVisualStyles();

  22:             Application.SetCompatibleTextRenderingDefault(false);

  23:             Application.Run(new xxxForm());

  24:             mutex.ReleaseMutex();

  25:         }

  26: else

  27:         {

  28:             Process currentProcess = Process.GetCurrentProcess();

  29:             Process[] procList = Process.GetProcessesByName(currentProcess.ProcessName);

  30:  

  31: foreach (Process proc in procList)

  32:             {

  33: // Found a running instance

  34: if (proc.Id != currentProcess.Id)

  35:                 {

  36: // Active the running instance

  37:                     ShowWindowAsync(proc.MainWindowHandle, WS_SHOWSTYLE);

  38:                     SetForegroundWindow(proc.MainWindowHandle);

  39:  

  40: break;

  41:                 }

  42:             }

  43:  

  44:             Application.Exit();

  45:         }

  46:     }