C#FORM只允许启动一个进程

SingleInstance类

using System;
using System.Collections.Generic;
using System.Text;

using System.Threading;
using System.Reflection;
using System.Runtime.InteropServices;// win API 引用
using System.Diagnostics;//Process

namespace QueuerServer
{
    /**//// <summary>
    /// 使应用程序仅运行一个实例。
    /// </summary>
    static class SingleInstance
    {
        [DllImport("User32.dll")]
        private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);
        [DllImport("User32.dll")]
        private static extern bool SetForegroundWindow(IntPtr hWnd);

        private static Mutex mutex = null;

        public static bool CreateMutex()
        {
            return CreateMutex(Assembly.GetEntryAssembly().FullName);
        }

        public static bool CreateMutex(string name)
        {
            bool result = false;
            mutex = new Mutex(true, name, out result);
            return result;
        }

        public static void ReleaseMutex()
        {
            if (mutex != null)
            {
                mutex.Close();
            }
        }

        /**//// <summary>
        /// ShowWindow() Commands
        /// </summary>
        private const int SW_HIDE = 0;
        private const int SW_SHOWNORMAL = 1;
        private const int SW_NORMAL = 1;
        private const int SW_SHOWMINIMIZED = 2;
        private const int SW_SHOWMAXIMIZED = 3;
        private const int SW_MAXIMIZE = 3;
        private const int SW_SHOWNOACTIVATE = 4;
        private const int SW_SHOW = 5;
        private const int SW_MINIMIZE = 6;
        private const int SW_SHOWMINNOACTIVE = 7;
        private const int SW_SHOWNA = 8;
        private const int SW_RESTORE = 9;
        private const int SW_SHOWDEFAULT = 10;
        private const int SW_FORCEMINIMIZE = 11;
        private const int SW_MAX = 11;

        /**//// <summary>
        /// 激活同Instance窗体
        /// </summary>
        /// <param name="instance"></param>
        /// <returns></returns>
        public static bool HandleRunningInstance(Process instance)
        {
            //确保窗口没有被最小化或最大化 
            ShowWindowAsync(instance.MainWindowHandle, SW_MAXIMIZE);
            //设置为foreground window 
            return SetForegroundWindow(instance.MainWindowHandle);
        }

        public static bool HandleRunningInstance()
        {
            Process p = GetRunningInstance();
            if (p != null)
            {
                HandleRunningInstance(p);
                return true;
            }
            return false;
        }

        /**//// <summary>
        /// 获取应用程序进程实例,如果没有匹配进程，返回Null值
        /// </summary>
        /// <returns></returns>
        public static Process GetRunningInstance()
        {
            Process currentProcess = Process.GetCurrentProcess(); //获取当前进程
            //获取当前运行程序完全限定名 
            string currentFileName = currentProcess.MainModule.FileName;
            //获取进程名为ProcessName的Process数组。 
            Process[] processes = Process.GetProcessesByName(currentProcess.ProcessName);
            //遍历有相同进程名称正在运行的进程 
            foreach (Process process in processes)
            {
                if (process.MainModule.FileName == currentFileName)
                {
                    if (process.Id != currentProcess.Id) //根据进程ID排除当前进程 
                        return process;//返回已运行的进程实例 
                }
            }
            return null;
        }
    }
}

主工程中：

namespace QueuerServer
{
    static class Program
    {
        private static MainForm m_MainForm;
        public static MainForm MainForm
        {
            get { return Program.m_MainForm; }
        }

        /**//// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main(string[] args)
        {
            #region
            bool autoStart = false;
            bool hide = false;
            bool service = false;
            foreach (string arg in args)
            {
                //MessageBox.Show(arg);
                string command = arg.Trim().ToLower();
                //if(arg.Trim().ToLower().Equals("-autostart"))
                switch (command)
                {
                    case "-autostart":
                        autoStart = true;
                        break;
                    case "-hide":
                        hide = true;
                        break;
                    case "-service":
                        service = true;
                        break;
                    default:
                        break;
                }
            }
            #endregion

            //使应用程序只能生成一个进程
            if (SingleInstance.CreateMutex())
            {
                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);

                RunMainForm(autoStart, hide, service);
                SingleInstance.ReleaseMutex();
            }
            else//若已经运行了一个进程，则激活该进程。
            {
                //MessageBox.Show("程序已经运行！");
                SingleInstance.HandleRunningInstance();
            }

            //Application.EnableVisualStyles();
            //Application.SetCompatibleTextRenderingDefault(false);
            //Application.Run(new MainForm(autoStart, hide, service));
        }


        private static void RunMainForm(bool autoStart, bool hide, bool service)
        {
            try
            {
                CreateMainForm(autoStart, hide, service);
            }
            catch (Exception e)
            {
                if (DialogResult.OK == MessageBox.Show(e.Message, "应用程序错误", MessageBoxButtons.OKCancel))
                {
                    //这是一个重新启动机制，但是丢失全部应用程序信息。
                    RunMainForm(autoStart, hide, service);
                }
                //XMLMessageManager.WriteExceptionToLog(e);
            }
        }

        private static void CreateMainForm(bool autoStart, bool hide, bool service)
        {
            if (m_MainForm != null)
            {
                m_MainForm.Dispose();
                m_MainForm = null;
            }
            m_MainForm = new MainForm(autoStart, hide, service);
            Application.Run(m_MainForm);
        }
    }
}