Asp.net通过IP地址获得域名信息

时间：2011-03-23 来源：苍马之子

本段代码可以获取本机的IP地址，并可以根据IP地址获取本机所在域域名：

.aspx代码：

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>无标题页</title>
    <style type="text/css">
        .style1
        {
            width: 600px;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <div style="text-align:center;">

    <table class="style1">
        <tr>
            <td colspan="2" style="text-align:center;">
    <font face="宋体">
     <asp:Label id="Label1"
             runat="server">通过域名获得IP地址</asp:Label></font>
            </td>
        </tr>
        <tr>
            <td colspan="2" style="text-align:center;">
    <font face="宋体">
     <asp:TextBox id="TextBox1"  runat="server"
      Width="248px"></asp:TextBox>
                </font>
            </td>
        </tr>
        <tr>
            <td  style="text-align:center;">
        <font face="宋体">
     <asp:Button id="TOIP"  runat="server" Text="转化为IP" onclick="TOIP_Click"></asp:Button>
        </font>
            </td>
            <td style="text-align:center;">
    <font face="宋体">
     <asp:Button id="TOAD" runat="server"
      Text="转化为域名" onclick="TOAD_Click"></asp:Button>
     </font>
            </td>
        </tr>
        <tr>
            <td colspan="2" style="text-align:center;">
        <font face="宋体">
     <asp:Label id="Label2"  runat="server"></asp:Label>
        </font>
            </td>
        </tr>
    </table>
      </div>
    </form>
</body>
</html>

.aspx.cs代码

1 using System;
2 using System.Configuration;
3 using System.Data;
4 using System.Linq;
5 using System.Web;
6 using System.Web.Security;
7 using System.Web.UI;
8 using System.Web.UI.HtmlControls;
9 using System.Web.UI.WebControls;
10 using System.Web.UI.WebControls.WebParts;
11 using System.Xml.Linq;
12 using System.Net;
13
14 public partial class _Default : System.Web.UI.Page
15 {
16     protected void Page_Load(object sender, EventArgs e)
17     {
18         // 在此处放置用户代码以初始化页面
19       //  Dns dns;
20         string hostname = Dns.GetHostName();
21         IPAddress[] ip = Dns.Resolve(hostname).AddressList;
22         Label2.Text = "机器名称：" + hostname.ToString() + "<br>IP地址：" + ip[0].ToString();
23
24     }
25
26       //转化为IP地址
27     protected void TOIP_Click(object sender, EventArgs e)
28     {
29         IPHostEntry hostInfo = Dns.GetHostByName(TextBox1.Text);
30         Label2.Text = hostInfo.AddressList[0].ToString();
31         TextBox1.Text = hostInfo.AddressList[0].ToString();
32
33     }
34
35     //转化为域名
36     protected void TOAD_Click(object sender, EventArgs e)
37     {
38        if(this.TextBox1.Text!="")
39         {
40         IPHostEntry hostInfo = Dns.GetHostByAddress(TextBox1.Text);
41         Label2.Text = hostInfo.HostName;
42         }
43         else
44         {
45          Response.Write("<script> alert('请指定IP地址')</script>");
46         }
47     }
48 }