c#防软件多开源码

打开program.cs启动文件, 修改里面的代码:

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Runtime.InteropServices;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp3
{
    internal static class Program
    {
        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            bool createdNew;
            Mutex mutex = new Mutex(true, "MyAppMutexabc", out createdNew);
            if (!createdNew)
            {
                // 应用程序已经在运行中，激活其主窗口
                Process[] processes = Process.GetProcessesByName(Process.GetCurrentProcess().ProcessName);
                if (processes.Length > 0)
                {
                    Process process = processes[0];
                    ShowWindowAsync(process.MainWindowHandle, SW_RESTORE);
                    SetForegroundWindow(process.MainWindowHandle);
                }
                return;
            }
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new mainForm());//Form1
            mutex.ReleaseMutex();
        }

        [DllImport("user32.dll")]
        static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);

        [DllImport("user32.dll")]
        static extern bool SetForegroundWindow(IntPtr hWnd);

        const int SW_RESTORE = 9;
    }
}