/// <summary>

 /// 获取本机公网IP

 /// </summary>

 /// <returns></returns>

 public static string GetIP_Lan()

 {

     string tempip = "127.0.0.1";

     try

     {

         WebRequest wr = WebRequest.Create("http://www.ip138.com/ip2city.asp");

         Stream s = wr.GetResponse().GetResponseStream();

         StreamReader sr = new StreamReader(s, Encoding.Default);

         string all = sr.ReadToEnd();

         int start = all.IndexOf("[") + ;

         int end = all.IndexOf("]", start);

         tempip = all.Substring(start, end - start);

         sr.Close();

         s.Close();

     }

     catch

     {

     }

     return tempip;

 }