C#获得外网的IP地址

1 static string GetIP()

2 {

//http://www.ip138.com/ip2city.asp

3 Uri uri = new Uri("http://www.ikaka.com/ip/index.asp");

4 System.Net.HttpWebRequest req = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(uri);

5 req.Method = "POST";

6 req.ContentType = "application/x-www-form-urlencoded";

7 req.ContentLength = 0;

8 req.CookieContainer = new System.Net.CookieContainer();

9 req.GetRequestStream().Write(new byte [0], 0, 0);

10 System.Net.HttpWebResponse res = (System.Net.HttpWebResponse)(req.GetResponse());

11 StreamReader rs = new StreamReader(res.GetResponseStream(), System.Text.Encoding.GetEncoding("GB18030"));

12 string s = rs.ReadToEnd();

13 rs.Close();

14 req.Abort();

15 res.Close();

16 System.Text.RegularExpressions.Match m = System.Text.RegularExpressions.Regex.Match(s, @"IP：\[(?<IP>[0-9\.]*)\]");

17 if (m.Success) return m.Groups["IP"].Value;

18 return string.Empty;

19 }