PEIS/Update/Program.cs

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

namespace Update
{
    static class Program
    {
        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            var program = "PEIS.exe";

            // 检查程序是否正在运行
            Process[] processes = Process.GetProcessesByName(program);

            if (processes.Length > 0)
            {
                // 关闭程序
                foreach (var process in processes)
                {
                    process.Kill();
                    process.WaitForExit(); // 等待程序退出
                    Console.WriteLine($@"Closed existing instance of {program}");
                }

                // 等待2秒
                Thread.Sleep(1000);
            }
            Application.Run(new Form1());
        }
    }
}