Why is my consule application faster then my forms application

See more:

C#

forms

console

Hi guys,

I have written a code for my forms application, this application scans all active IP's in a big range using PING.ASYNC. I used a windows MSDN exmaple for this.

When i run this code in my forms application some ping returns with a delay of +/- 10 seconds, or worse some never...

When i run the EXACT the same code with a consule application all my result get back within a timespan of 500 milleseconds.

Code example consule :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Siemens;
using IPScanner;

namespace ConsuleInterface
{
    class Program
    {
        static void Main(string[] args)
        {
            Scanner Scanner = new Scanner();
            StringBuilder Scanlist = new StringBuilder();
            Console.WriteLine("Start scan, please wait");
            Scanlist = Scanner.Find("192.168.0.1");
            Console.Write(Scanlist);
            Console.ReadKey();
        }
    }
}

Code example forms :

private void BTN_Scan_IP_Range_Click(object sender, EventArgs e)
{
   TxtDump.Text = "";
   TxtDump.Text = "Starting scan, please wait for 20 seconds for results";
   TxtDump.Text = Scanner.Find(IP_Adres_PLC.Text).ToString();
    //Scan Scan = new Scan();
    //TxtDump.Text = Scan.Start(IP_Adres_PLC.Text).ToString();
}

Source code :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Net;
using System.Net.Sockets;
using System.Net.NetworkInformation;
using Siemens;
using System.Diagnostics;
using System.Threading;
using System.Runtime.InteropServices;


namespace IPScanner
{
    public class Scanner
    {
        static CountdownEvent countdown;
        static int upCount = 0;
        static object lockObj = new object();
        const bool resolveNames = false;
        static StringBuilder Scanlist = new StringBuilder();

        public StringBuilder Find(string IpAdress)
        {
            string[] IPV6 = IpAdress.Split(new char[] { ':' });
            if (IPV6.Length == 1) // ipv4 or hostname
            {
                                // check format of ipadres - should be a.b.c.d
                string[] IPV4 = IpAdress.Split(new char[] { '.' });
                if (IPV4.Length <= 3)
                {
                    return Scanlist.AppendLine("Invalid IP adress entered, please enter a valid ip adres. Example: (IPv4) 192.168.1.1");                    
                }
                // Check for digits and dots
                foreach (Char c in IpAdress.ToCharArray())
                {
                    if (Char.IsDigit(c)) continue;
                    else if (c == '.') continue;
                    else return Scanlist.AppendLine("Invalid IP adress entered, please enter a valid ip adres. Example: (IPv4) 192.168.1.1");      
                }
                countdown = new CountdownEvent(1);
                Stopwatch sw = new Stopwatch();
                sw.Start();
                for (int i = 1; i <= 254; i++)
                {
                    string IP = string.Format("{0}.{1}.{2}.{3}", IPV4[0], IPV4[1], IPV4[2], i);

                    Ping p = new Ping();
                    p.PingCompleted += new PingCompletedEventHandler(p_PingCompleted);
                    countdown.AddCount();
                    p.SendAsync(IP, 100, IP);
                }
                countdown.Signal();
                countdown.Wait();
                sw.Stop();
                TimeSpan span = new TimeSpan(sw.ElapsedTicks);
                Scanlist.AppendLine(String.Format("Took {0} milliseconds. {1} hosts active.", sw.ElapsedMilliseconds, upCount));
                return Scanlist;
            }
            else if (IPV6.Length > 2) //ipv6
            {
                return Scanlist.AppendLine("IPv6 is not supported yet");      
            }
            else
            {
                return Scanlist.AppendLine("Invalid IP adress entered, please enter a valid ip adres. Example: (IPv4) 192.168.1.1 or (IPv6) 3ffe:6a88:85a3:08d3:1319:8a2e:0370:7344");      
            }
        }
        public void p_PingCompleted(object sender, PingCompletedEventArgs e)
        {
            S7CpuInfo CPU_Info = new S7CpuInfo();
            string ip = (string)e.UserState;
            if (e.Reply != null && e.Reply.Status == IPStatus.Success)
            {
                string mac = getMAC(IPAddress.Parse(ip));
                Scanlist.AppendLine(string.Format("{0} is online - MAC adres - {1} - response time {2} ms)", ip, mac, e.Reply.RoundtripTime));
                if (Global.PLC.ConnectTo(ip,0,2) == 0)
                {
                    Global.PLC.GetCpuInfo(CPU_Info);
                    string cpuname = "", cputype = "";
                    cpuname = CPU_Info.ModuleName(); cputype = CPU_Info.ModuleTypeName();
                    Scanlist.AppendLine(string.Format("Siemens PLC found - Type {0} -  PLC name {1}", cputype, cpuname));
                }
                else
                {
                    Scanlist.AppendLine(string.Format("Not an Siemens PLC"));
                }
                upCount++;
            }
            else if (e.Reply == null)
            {
                Scanlist.AppendLine(string.Format("Pinging {0} failed. (Null Reply object?)", ip));
            }
            countdown.Signal(1);
        }

        [DllImport("iphlpapi.dll", ExactSpelling = true)]
        public static extern int SendARP(int DestIP, int SrcIP, byte[] pMacAddr, ref uint PhyAddrLen);

        public static string getMAC(IPAddress address)
        {
            int intAddress = BitConverter.ToInt32(address.GetAddressBytes(), 0);

            byte[] macAddr = new byte[6];
            uint macAddrLen = (uint)macAddr.Length;
            if (SendARP(intAddress, 0, macAddr, ref macAddrLen) != 0)
                return "(NO ARP result)";

            string[] str = new string[(int)macAddrLen];
            for (int i = 0; i < macAddrLen; i++)
                str[i] = macAddr[i].ToString("x2");

            return string.Join(":", str);
            ;
        }
    }
}

Why is the consule so much faster?
How can i speed up my windows forms application?

Hope you guys can give me some answers, thanks in advance!