Ping Sweep

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Net.Sockets;
using System.IO;
using System.Net;
using System.Runtime.InteropServices;
 
 
namespace pingsweep
{
     public partial class Form1 : Form
    {
        //StreamWriter sw = new StreamWriter(null, "c:\output.txt");
        ping PING = new ping();
 
        public Form1()
        {
            InitializeComponent();
 
        }
        public UInt32 convertIPtoLong(string ip)
        {
            string[] digits;
            digits = ip.Split(".".ToCharArray());
            return Convert.ToUInt32(
                    Convert.ToUInt32(digits[3]) * Math.Pow(2, 24) +
                    Convert.ToUInt32(digits[2]) * Math.Pow(2, 16) +
                    Convert.ToUInt32(digits[1]) * Math.Pow(2, 8) +
                    Convert.ToUInt32(digits[0]));
        }
        public string describeResponse(uint code)
        {
            string Rcode = "";
            switch (code)
            {
                case 0: Rcode = "Success"; break;
                case 11001: Rcode = "Buffer too Small"; break;
                case 11002: Rcode = "Dest Network Not Reachable"; break;
                case 11003: Rcode = "Dest Host Not Reachable"; break;
                case 11004: Rcode = "Dest Protocol Not Reachable"; break;
                case 11005: Rcode = "Dest Port Not Reachable"; break;
                case 11006: Rcode = "No Resources Available"; break;
                case 11007: Rcode = "Bad Option"; break;
                case 11008: Rcode = "Hardware Error"; break;
                case 11009: Rcode = "Packet too Big"; break;
                case 11010: Rcode = "Rqst Timed Out"; break;
                case 11011: Rcode = "Bad Request"; break;
                case 11012: Rcode = "Bad Route"; break;
                case 11013: Rcode = "TTL Exprd in Transit"; break;
                case 11014: Rcode = "TTL Exprd Reassemb"; break;
                case 11015: Rcode = "Parameter Problem"; break;
                case 11016: Rcode = "Source Quench"; break;
                case 11017: Rcode = "Option too Big"; break;
                case 11018: Rcode = " Bad Destination"; break;
                case 11019: Rcode = "Address Deleted"; break;
                case 11020: Rcode = "Spec MTU Change"; break;
                case 11021: Rcode = "MTU Change"; break;
                case 11022: Rcode = "Unload"; break;
                case 11050: Rcode = "General Failure"; break;
            }
            return Rcode;
        }
 
        private void btnAbout_Click(object sender, EventArgs e)
        {
            MessageBox.Show("A simple ping sweep / whois app by Evil1", "About");
        }
 
        private void btnDie_Click(object sender, EventArgs e)
        {
           // void killit(); method to kill my shit for multithreading
            Application.Exit();
        }
 
        private void btnStart_Click(object sender, EventArgs e)
        {
            uint LongIP;
            string buffer;
            UInt32 hIP;
            uint timeout;
            buffer = new StringBuilder().Append(' ', 32).ToString();
            LongIP = convertIPtoLong(txtStartingIP.Text);
 
            hIP = PING.IcmpCreateFile();
 
            PING.pIPo.TTL = 255;
            timeout = 2700;
            PING.IcmpSendEcho(hIP, LongIP, buffer,
                       (uint)buffer.Length,
                       ref PING.pIPo, ref PING.pIPe,
                       (uint)Marshal.SizeOf(PING.pIPe) + 8,
                       timeout);
            MessageBox.Show(describeResponse(PING.pIPe.Status));
 
 
        }
    }
    public class ping
    {
        public struct IP_OPTION_INFORMATION
        {
            public byte TTL, Tos, Flags, OptionSize;
            [System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.ByValTStr, SizeConst = 128)]
            public string OptionsData;
        }
        public struct ICMP_ECHO_REPLY
        {
            public uint Address, Status, RoundTripTime;
            public ushort DataSize, Reserved;
            public IP_OPTION_INFORMATION Options;
        }
        [System.Runtime.InteropServices.DllImport("icmp.dll", SetLastError = true)]
        public static extern uint IcmpSendEcho(
          uint IcmpHandle,
          uint DestAddress,
          string RequestData,
          uint RequestSize,
          ref IP_OPTION_INFORMATION RequestOptns,
          ref ICMP_ECHO_REPLY ReplyBuffer,
          uint ReplySize,
          uint TimeOut);
        [System.Runtime.InteropServices.DllImport("icmp.dll", SetLastError = true)]
        public static extern uint IcmpCreateFile();
        public static IP_OPTION_INFORMATION pIPo;
        public static ICMP_ECHO_REPLY pIPe;
 
 
      /*  internal uint IcmpCreateFile()
        {
            throw new Exception("Error");
        }*/
    }
}