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

<script language="C#" runat=server>

protected void doClick(Object Src, EventArgs E){

IPHostEntry hostInfo = DNS.GetHostByAddr(txtIP.Text);

showmsg.Text=hostInfo.Hostname;

}

</script>

<asp:Label runat=server id=showmsg />

<form id=testForm runat=server>

要查找的IP地址：<asp:TextBox runat=server id=txtIP /><asp:Button runat=server id=do Text="查找" onClick=doClick />

</form>