用post请求方式实现对地图服务的基本操作

ArcGIS Server REST API 中的很多操作都可以用以下方式实现，具体参数的设置请查看其中的详细说明

   public List<string> getGeometry(string CZAH, string url)
         {
             url += "/query";//query url
             string postString = "where=CZAH='" + CZAH + "'";//where
             //postString += "text=04CH88131210000004";
             postString += "&" + "returnGeometry=true";//returnGeometry
             postString += "&" + "f=json";//json
             string result = getPostData(postString, url);
             List<string> list = new List<string>();
             var result1 = JsonConvert.DeserializeObject<dynamic>(result);//添加Newtonsoft.Json类库并引用;
             var list1 = result1.features as IEnumerable<dynamic>;
             dynamic[] jsonfea = list1.ToArray();
             for (int i = ; i < jsonfea.Length; i++)
             {
                 list.Add(jsonfea[i].geometry.ToString());
             }
             return list;
         }

         /// <summary>
         /// 获取post后的返回值
         /// </summary>
         /// <param name="postString">POST String</param>
         /// <param name="url">Post URL</param>
         /// <returns></returns>
         public string getPostData(string postString, string url)
         {
             string result = "";
             try
             {
                 byte[] postData = Encoding.UTF8.GetBytes(postString);
                 WebClient webClient = new WebClient();
                 string method = "POST";
                 //POST Header
                 webClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
                 //webClient.Headers.Add("Cache-Control", "no-cache");
                 //同步提交请求，并返回数据
                 byte[] responseData = webClient.UploadData(url, method, postData);//得到返回字符流
                 result = Encoding.UTF8.GetString(responseData);//解码
             }
             catch (Exception)
             {
                 throw;
             }
             return result;
         }