如何让应用程序仅运行一个实例(c#)

主要的思想非常简单,就是检查当前运行的进程里是否有现在要启动的应用程序的进程名称,如果有,查找两个进程的exe文件路径是否相同,如果相同,则让已运行的进程作为当前运行进程即可!
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Reflection; 
 [STAThread]
  static void Main()
  {
   //Application.Run(new UIForm());

            //得到正在运行的例程
            Process instance = RunningInstance();
            if (instance == null)
            {
                //如果没有其它例程,就新建一个窗体
                Application.Run(new UIForm());
            }
            else
            {
                //处理发现的例程
                HandleRunningInstance(instance);
            }

  }

        public static string GetMainPath(string strPath)
        {
            string[] ArrStr = strPath.Split('\\');

            string str = "";

            for (int i = 0; i < ArrStr.Length - 1; i++)
            {
                str += ArrStr[i];
            }

            return str;
        }

        public static Process RunningInstance()
        {
            Process current = Process.GetCurrentProcess();
            Process[] processes = Process.GetProcessesByName("AsynchUI");

            //遍历正在有相同名字运行的例程
            foreach (Process process in processes)
            {
                //忽略现有的例程
                if (process.Id != current.Id)
                {
                    //确保例程从EXE文件运行
                    if (GetMainPath(process.MainModule.FileName.Replace("/","\\")) ==
                      GetMainPath(Application.ExecutablePath.Replace("/", "\\")))
                    {
                        //返回另一个例程实例
                        return process;
                    }
                }
            }

            //没有其它的例程,返回Null
            return null;
        }

        public static void HandleRunningInstance(Process instance)
        {
            //确保窗口没有被最小化或最大化
            ShowWindowAsync(instance.MainWindowHandle, WS_SHOWNORMAL);

            //设置真实例程为foreground window
            SetForegroundWindow(instance.MainWindowHandle);
        }

        [DllImport("User32.dll")]

        private static extern bool ShowWindowAsync(
          IntPtr hWnd, int cmdShow);
        [DllImport("User32.dll")]
        private static extern bool
        SetForegroundWindow(IntPtr hWnd);
        private const int WS_SHOWNORMAL = 1;

原文地址:https://www.cnblogs.com/wpf123/p/2052928.html