根据ip获取用户地理位置

各大网站都提供根据ip获取用户地理位置信息，这里以新浪的接口为例子

接口地址为：http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=js&ip=218.18.171.146

代码：

         #region 根据ip获取地点
         /// 获取Ip归属地
         /// </summary>
         /// <param name="ip">ip</param>
         /// <returns>归属地</returns>
         public static string GetIpAddress(string ip)
         {
             JavaScriptSerializer Jss = new JavaScriptSerializer();
             //http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=js&ip=218.18.171.146 调用新浪的接口
             //var remote_ip_info = {"ret":1,"start":-1,"end":-1,"country":"\u4e2d\u56fd","province":"\u5e7f\u4e1c","city":"\u6df1\u5733","district":"","isp":"","type":"","desc":""};
             string address = string.Empty;
             try
             {
                 string reText = WebRequestPostOrGet("http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=js&ip="+ip, "");
                 reText = reText.Split('=')[].Split(';')[].Trim();
                 Dictionary<string, object> DicText = (Dictionary<string, object>)Jss.DeserializeObject(reText);
                 address = DicText["city"].ToString();
             }
             catch { }
             return address;
         }
         #endregion

其中WebRequestPostOrGet方法:

         #region Post/Get提交调用抓取
         /// <summary>
         /// Post/get 提交调用抓取
         /// </summary>
         /// <param name="url">提交地址</param>
         /// <param name="param">参数</param>
         /// <returns>string</returns>
         public static string WebRequestPostOrGet(string sUrl, string sParam)
         {
             byte[] bt = System.Text.Encoding.UTF8.GetBytes(sParam);

             Uri uriurl = new Uri(sUrl);
             HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(uriurl);//HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url + (url.IndexOf("?") > -1 ? "" : "?") + param);
             req.Method = "Post";
             req.Timeout =  * ;
             req.ContentType = "application/x-www-form-urlencoded;";
             req.ContentLength = bt.Length;

             using (Stream reqStream = req.GetRequestStream())//using 使用可以释放using段内的内存
             {
                 reqStream.Write(bt, , bt.Length);
                 reqStream.Flush();
             }
             try
             {
                 using (WebResponse res = req.GetResponse())
                 {
                     //在这里对接收到的页面内容进行处理 

                     Stream resStream = res.GetResponseStream();

                     StreamReader resStreamReader = new StreamReader(resStream, System.Text.Encoding.UTF8);

                     string resLine;

                     System.Text.StringBuilder resStringBuilder = new System.Text.StringBuilder();

                     while ((resLine = resStreamReader.ReadLine()) != null)
                     {
                         resStringBuilder.Append(resLine + System.Environment.NewLine);
                     }

                     resStream.Close();
                     resStreamReader.Close();

                     return resStringBuilder.ToString();
                 }
             }
             catch (Exception ex)
             {
                 return ex.Message;//url错误时候回报错
             }
         }
         #endregion Post/Get提交调用抓取