How To Get IP Address Of A Machine

 Getting the Host name and IP Address of Local Machine:

namespace NKUtilities 
{
    using System;
    using System.Net;
    
    public class DNSUtility
    {
        public static int Main (string [] args)
        {
        
          String strHostName = new String ("");
          if (args.Length == 0)
          {
              // Getting Ip address of local machine...

              // First get the host name of local machine.

              strHostName = DNS.GetHostName ();
              Console.WriteLine ("Local Machine's Host Name: " +  strHostName);
          }
          else
          {
              strHostName = args[0];
          }
          
          // Then using host name, get the IP address list..

          IPHostEntry ipEntry = DNS.GetHostByName (strHostName);
          IPAddress [] addr = ipEntry.AddressList;
          
          for (int i = 0; i < addr.Length; i++)
          {
              Console.WriteLine ("IP Address {0}: {1} ", i, addr[i].ToString ());
          }
          return 0;
        }    
     }
}

Getting the Local Machine's IP Address: 

 using System;
using System.Net;

class Test {

public static void Main() {
   IPAddress[] a = Dns.GetHostByName(Dns.GetHostName()).AddressList;
   for (int i=0; i<a.Length; i++)
      Console.WriteLine ("IpAddr[{0}]={1}",i,a[i]); }

}

For Any Host by using the site address:

using System;
// using the System.Net namespace
using System.Net;
class Class1
{

[STAThread]
static void Main(string[] args)
{
// Request the name
Console.Write("Please type the name of the host: ");
// Store it in 'host'
string host = Console.ReadLine();
try
{
// Get the DNS information
IPHostEntry ipHost = Dns.GetHostByName(host);
// Display the host name
Console.WriteLine("Host name: {0}", ipHost.HostName);
// Store the list of IP adresses
IPAddress[] ipAddr = ipHost.AddressList;
// Loop to actually display the IP
for(int x = 0; x < ipAddr.Length; x++)
{
Console.WriteLine("IP address: {0}", ipAddr[x].ToString());
}
}
// Catch the exception (if host was not found)
catch(System.Net.Sockets.SocketException)
{
Console.WriteLine("Host not found.");
}
}
}