Get Hostname from IP

bekim · October 8th, 2004, 02:16 AM

I saw this question in Classic ASP but I want this answer in ASP.NET.

Get hostname from IP.
Is there any way in ASP.NET to resolve a hostname from a given IP address? (in VB.NET)

Thank you.

stu9820 · October 8th, 2004, 07:11 AM

<%@ Import Namespace="System.Net" %>

<Script runat="Server">

Sub Button_Click( s As Object, e As EventArgs )
  Dim objIPHostEntry As IPHostEntry

  objIPHostEntry = Dns.GetHostByAddress( txtIP.Text )
  lblHostName.Text = objIPHostEntry.HostName
End Sub

</Script>

<html>
<head><title>Dns.aspx</title></head>

<form runat="Server">

<h2>Enter an IP Address:</h2>

<asp:TextBox
  id="txtIP"
  Runat="Server" />

<asp:Button
  Text="Submit!"
  OnClick="Button_Click"
  Runat="Server" />

<p>
<asp:Label
  id="lblHostName"
  EnableViewState="False"
  Runat="Server" />

</form>
</body>
</html>

bekim · October 8th, 2004, 07:53 PM

Hello stu9820
Thanks for your reply. But when I tried out your code the label is blank. It doens't return the hostname of the IP address I entered. What could be wrong?

stu9820 · October 11th, 2004, 09:38 AM

Did you press the submit button?