C#重新启动时，关闭较早的进程

WPF程序重新启动，如果有客户端进程存在，则关闭较早的进程

  　　　　private static System.Threading.Mutex mutex;
         public App()
         {
             this.Startup += new StartupEventHandler(App_Startup);
         }
         /// <summary>
         /// 登陆前判断是否存在客户端进程
         /// </summary>
         void App_Startup(object sender, StartupEventArgs e)
         {
             bool ret;
             mutex = new System.Threading.Mutex(true, "TCClient", out ret);
             Logger.D("打印有没有重复进程：",(!ret).ToString());
             if (!ret)
             {
                 Process process = Process.GetCurrentProcess();//后运行的程序
                 foreach (Process p in Process.GetProcessesByName("TCClient"))
                 {
                     //不是同一进程并且本进程启动时间最晚,则关闭较早进程
                     if (p.Id != process.Id && (p.StartTime - process.StartTime).TotalMilliseconds <= )
                     {
                          p.Kill();
                         //Application.Current.Shutdown(-1);
                          Thread.Sleep();
                         return;
                     }
                 }

                 //MessageBox.Show("已存在一个本客户端进程在运行，请手动关闭后再重新启动", "系统提示", MessageBoxButton.OK);
                 //Environment.Exit(0);
             }

         }