using System.Text.RegularExpressions;
using System.Diagnostics;
public class test
{
        public test
        {}
        public static string GetCustomerMac(string IP) //para IP is the client\'s IP 
        { 
               string dirResults=\"\"; 
               ProcessStartInfo psi  = new ProcessStartInfo(); 
               Process proc = new Process(); 
               psi.FileName = \"nbtstat\"; 
               psi.RedirectStandardInput = false; 
               psi.RedirectStandardOutput = true; 
               psi.Arguments = \"-A \" + IP; 
               psi.UseShellExecute = false; 
               proc = Process.Start(psi); 
               dirResults = proc.StandardOutput.ReadToEnd(); 
               proc.WaitForExit(); 
               dirResults=dirResults.Replace(\"/r\",\"\").Replace(\"/n\",\"\").Replace(\"/t\",\"\");

              Regex reg=new Regex(\"Mac[ ]{0,}Address[ ]{0,}=[ ]{0,}(?<key>((.)*?)) __MAC\",RegexOptions.IgnoreCase|RegexOptions.Compiled); 
               Match mc=reg.Match(dirResults+\"__MAC\");

           if(mc.Success) 
            { 
                return mc.Groups[\"key\"].Value; 
           } 
            else 
           { 
                reg=new Regex(\"Host not found\",RegexOptions.IgnoreCase|RegexOptions.Compiled); 
                mc=reg.Match(dirResults); 
            if(mc.Success) 
            { 
                 return \"Host not found!\"; 
            } 
            else 
            { 
                 return \"\"; 
            } 
       }
  }
}