C#程序防多开又一法

using System;
using System.Diagnostics;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace TestCallAPIRefreshPolicy
{
    static class Program
    {
        [STAThread]
        static void Main()
        {
            Guid ownGUID = new Guid(((GuidAttribute)Attribute.GetCustomAttribute(Assembly.GetExecutingAssembly(), typeof(GuidAttribute))).Value);
            int ownPID = Process.GetCurrentProcess().Id;

            foreach (Process p in Process.GetProcesses())
            {
                try
                {
                    //这儿之所以用Assembly.Load(byte[])获得程序集是因为该方法不会锁住文件
                    Guid proGUID = new Guid(((GuidAttribute)Attribute.GetCustomAttribute(Assembly.Load(File.ReadAllBytes(p.MainModule.FileName)), typeof(GuidAttribute))).Value);
                    if (ownGUID == proGUID && ownPID != p.Id)
                    {
                        MessageBox.Show("程序已运行");
                        return;
                    }
                }
                catch { }//访问某些进程的MainModule会引发异常，必须波或
            }

            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new FmMain());
        }
    }
}