如果存在一些领域——如果它们有一只nt子,就会有 p子,则试图绘制一份域清单,以获得初步的标识。 不是问题,但出于某种原因,转头也指背。

因此,试图获得http://unter responce of the special url.,但不管怎样,我得到403份答复。 是否有任何想法?

private void hunt_Click(object sender, EventArgs e)
    {
        listBox1.Items.Clear();
        string hostAddress = txtKeyword.Text;
        string combined;

        string[] strArray = new string[] { ".com", ".net", ".org", ".ca", ".gov" };

        foreach (string str in strArray)
        {

            combined = hostAddress + str;


            string result = string.Empty;
            try
            {
                Ping ping = new Ping();
                int timeout = 1500;
                PingReply pingreply = ping.Send(combined, timeout);


                if (pingreply != null && pingreply.Status.ToString() != "TimedOut")
                {
                    result = "Address: " + pingreply.Address + "
"
                         + "Roundtrip Time: " + pingreply.RoundtripTime + "
"
                         + "TTL (Time To Live): " + pingreply.Options.Ttl + "
"
                         + "Buffer Size: " + pingreply.Buffer.Length + "
";

                    listBox1.Items.Add(combined + " " + result);
                }
                else
                {

                    listBox1.Items.Add(combined + " not found");
                }

            }


            catch (Exception pingError)
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www."+combined);
                request.Method = "HEAD";
                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                HttpStatusCode status = response.StatusCode;
                listBox1.Items.Add(status);
            }

        }
    }

thanks in advance

EDIT Ping error as follows:

System.Net.NetworkInformation.PingException: An exception occurred during a Ping     request. ---> System.Net.Sockets.SocketException: No such host is known
   at System.Net.Dns.GetAddrInfo(String name)
   at System.Net.Dns.InternalGetHostByName(String hostName, Boolean includeIPv6)
   at System.Net.Dns.GetHostAddresses(String hostNameOrAddress)
   at System.Net.NetworkInformation.Ping.Send(String hostNameOrAddress, Int32 timeout,     Byte[] buffer, PingOptions options)
   --- End of inner exception stack trace ---
   at System.Net.NetworkInformation.Ping.Send(String hostNameOrAddress, Int32 timeout,     Byte[] buffer, PingOptions options)
   at System.Net.NetworkInformation.Ping.Send(String hostNameOrAddress, Int32 timeout)
   at DomainHunter.Form1.hunt_Click(Object sender, EventArgs e) in