CrazyPingTest

using System;
using System.Net.NetworkInformation;
using System.Runtime.InteropServices;
using System.Threading;

namespace ErmineMD.CrazyPingTest
{
    class Program
    {
        #region Trap application termination
        // https://stackoverflow.com/questions/474679/capture-console-exit-c-sharp
        [DllImport("Kernel32")]
        private static extern bool SetConsoleCtrlHandler(EventHandler handler, bool add);

        private delegate bool EventHandler(CtrlType sig);
        static EventHandler exitHandler;

        enum CtrlType
        {
            CTRL_C_EVENT = 0,
            CTRL_BREAK_EVENT = 1,
            CTRL_CLOSE_EVENT = 2,
            CTRL_LOGOFF_EVENT = 5,
            CTRL_SHUTDOWN_EVENT = 6
        }

        static bool ExitHandler(CtrlType sig)
        {
            exiting = true;
            needToExit.WaitOne();
            needToExit.Dispose();
            return true;
        }
        #endregion

        static Random rand = new Random();
        static object randLocker = new object();
        static SemaphoreSlim semaphore = new SemaphoreSlim(300, 300);
        static bool exiting = false;
        static CountdownEvent countdown = new CountdownEvent(1);
        static AutoResetEvent needToExit = new AutoResetEvent(false);
        static int j = 1;
        static int index = 0;
        // $a = 1..254 | % {([string]$_).padleft(3)} | get-random -count 254; for ($i = 0; $i -lt $a.length; $i += 16) { ($a[$i..($i+15)] -join ', ') + ',' }
        static int[] array = {
            205, 106, 145,  54, 227,  38, 240,  22,  84, 249, 197,  61, 251, 231, 250, 103,
            112,  86,  47,  81, 136, 242,  64,  87, 222,  50,  19, 110, 125,   1, 244, 253,
             25, 144,  93,  52,  90,   4,  99,  16, 243, 129, 164, 160, 188, 190,  69, 206,
             44,  83,  79,   9, 209,  10,  23,  95, 175, 207,  89, 161,  39, 163, 141, 122,
             28, 213,  24, 111,  32,  12, 174, 123,  56,  30, 155, 237, 181, 196, 116, 121,
            166, 128,  27, 217,  62, 192,  34,   2, 194, 168, 224,  13,  33, 203,  88,  15,
            186, 219,   3, 210, 176, 204, 130, 171,  58,   6,  94, 211, 232, 208, 150,  36,
            179, 100,  51,  53, 254,  92, 235,  80, 228,  85,   5, 170,  35, 137,  49, 162,
            115, 173, 191, 199, 183, 238, 225,  73,  42, 154,  77,  76, 133, 113, 119, 214,
            195, 167, 229, 126, 153, 169,  46,  82, 124,  71,  63, 117, 236, 218, 220, 165,
             21, 245,  68, 135, 198, 234, 247, 157,  96, 156, 193, 233, 127, 143, 159,  17,
            230, 109,  70,  60,  65, 146,  40,  98, 182,  20, 101, 215,  41, 200,  59, 104,
            216, 239,  14,  78,  43, 148,  67, 108,  29, 185,  57,  66,  11, 212,  75, 131,
            184,  31,  91, 114, 134, 152, 105, 132, 189, 140,  37,  72,  18, 178,  26, 149,
            151, 138, 202, 147, 172, 158,  55, 248, 241, 118, 142,   8, 107, 201,  97, 187,
            177,  74, 226, 246, 139, 102, 120, 223,  45,   7, 252, 221,  48, 180 };
        static int arrayLen = array.Length;

        public static void MyPing()
        {
            int i;
            // Variant 1 - random order IP adresses
            /*lock (randLocker)
                i = rand.Next(1, 254);*/

            // Variant 2 - normal order IP adresses
            /*lock (randLocker)
            {
                i = j;
                if (j == 50)
                    j = 1;
                else
                    ++j;
            }*/

            // Variant 3 - fixed array of random IP adresses
            lock (randLocker)
            {
                i = array[index];
                if (index == arrayLen - 1)
                    index = 0;
                else
                    ++index;
            }


            string ipAddress = "192.168.1." + i;

            using (var ping = new Ping())
            {
                try
                {
                    Console.WriteLine(ipAddress.PadRight(20) + ">");
                    var reply = ping.Send(ipAddress, 1000);
                    Console.WriteLine(ipAddress.PadRight(20) + reply.Status.ToString());
                }
                catch (Exception ex)
                {
                    Console.WriteLine("Error!!! " + ipAddress + "    " + ex.Message);
                }
            }
            semaphore.Release();
            countdown.Signal();
        }

        static void Main(string[] args)
        {
            exitHandler += new EventHandler(ExitHandler);
            SetConsoleCtrlHandler(exitHandler, true);

            while (!exiting)
            {
                semaphore.Wait();
                countdown.AddCount();
                //Thread.Sleep(10);
                Thread t = new Thread(MyPing);
                t.Start();
            }

            countdown.Signal();
            countdown.Wait();
            countdown.Dispose();
            semaphore.Dispose();

            // Not necessary
            Console.WriteLine("--------------------------------------------------------- Exit ----");
            Thread.Sleep(1000);

            needToExit.Set();
        }
    }
}