Creating Single Instance of Your Application

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Threading;

namespace myappliaction
{
    static class Program
    {
        /// 

        /// The main entry point for the application.
        /// 
        [STAThread]
        static void Main()
        {
            bool createdNew = true;
            using (Mutex mutex = new Mutex(true, "myappliaction", out createdNew))
            {

                try
                {
                    if (createdNew)
                    {
                        Application.EnableVisualStyles();
                        Application.SetCompatibleTextRenderingDefault(false);
                        Application.Run(new mainform());
                    }
                    else
                    {
                        MessageBox.Show("Application is already running.", "Message", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
                        //Process current = Process.GetCurrentProcess();
                        //foreach (Process process in Process.GetProcessesByName(current.ProcessName))
                        //{
                        //    if (process.Id != current.Id)
                        //    {
                        //        SetForegroundWindow(process.MainWindowHandle);
                        //        break;
                        //    }
                        //}
                    }
                }
                catch (Exception exception)
                {
                    MessageBox.Show(exception.Message, "Message", MessageBoxButtons.OK, MessageBoxIcon.Hand);
                }
            }
        }
    }
}