//引用
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Web;
using Newtonsoft.Json.Linq;
using Newtonsoft.Json;
using ProvinceAPI.Model;
using System.Net.Security;

 private void chehui()
        {
            string token = "";
            string Year = "2019";
            string RegionID = "0";
            int DataType = 2;
            token = APIHelp.GetAccessToken().Data;

            string result = APIHelp.Post("外网url", token, RegionID, Year, DataType);
            
            Response.Write(result);



        }

        const string api_url = "http://外网url/";
        const string api_appid = "e453467af0c311e9";
        const string app_secret = "e453467af0c311e99d49fefcfe183302";

        public static AccessToken GetAccessToken()
        {
            string url = api_url + "Authorization/GetAccessToken?appID=" + api_appid + "&appSecret=" + app_secret;
            string result = GetHttpResponse(url, 5000);

            JObject obj = (JObject)JsonConvert.DeserializeObject(result);

            AccessToken token = new AccessToken();
            token.IsSuccess = (bool)obj["IsSuccess"];
            token.Message = (string)obj["Message"];
            token.Data = (string)obj["Data"];

            return token;
        }

   public static string Post(string url, string accesstoken, string RegionID, string Year, int DataType)
        {
           
            System.GC.Collect();//垃圾回收，回收没有正常关闭的http连接
            string result = "";//返回结果
            HttpWebRequest request = null;
            HttpWebResponse response = null;
            Stream reqStream = null;
            try
            {
                //设置最大连接数
                ServicePointManager.DefaultConnectionLimit = 200;
                /***************************************************************
                * 下面设置HttpWebRequest的相关属性
                * ************************************************************/
                request = (HttpWebRequest)WebRequest.Create(url);
                request.Method = "POST";
                //这个在Post的时候，一定要加上，如果服务器返回错误，他还会继续再去请求，不会使用之前的错误数据，做返回数据
                request.ServicePoint.Expect100Continue = false;
                //设置POST的数据类型和长度
                request.ContentType = "application/x-www-form-urlencoded;charset=gb2312";
                StringBuilder buffer = new StringBuilder();
                buffer.AppendFormat("&{0}={1}", "AccessToken", accesstoken);
                buffer.AppendFormat("&{0}={1}", "RegionID", RegionID);
                buffer.AppendFormat("&{0}={1}", "Year", Year);
                buffer.AppendFormat("&{0}={1}", "DataType", DataType);

                //StringBuilder buffer = new StringBuilder();
                //buffer.Append("{\"AccessToken\":\"" + accesstoken + "\",");
                //buffer.Append("\"RegionID\":\"" + RegionID + "\",");
                //buffer.Append("\"Year\":\"" + Year + "\",");
                //buffer.Append("\"DataType\":" + DataType + "}");
                //上面两种传参数的方式，本人试了json不行就用键值对的。
                byte[] data = System.Text.Encoding.UTF8.GetBytes(buffer.ToString());
                request.ContentLength = data.Length;
 
                //往服务器写入数据
                reqStream = request.GetRequestStream();
                reqStream.Write(data, 0, data.Length);
                reqStream.Close();
 
 
                //获取服务端返回
                response = (HttpWebResponse)request.GetResponse();
 
 
                //获取服务端返回数据
                StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
                result = sr.ReadToEnd().Trim();
                sr.Close();
            }
            catch (System.Threading.ThreadAbortException e)
            {
                //Log.Error("HttpService", "Thread - caught ThreadAbortException - resetting.");
                
                System.Threading.Thread.ResetAbort();
            }
            catch (WebException e)
            {
                //Log.Error("HttpService", e.ToString());
                //if (e.Status == WebExceptionStatus.ProtocolError)
                //{
                    //Log.Error("HttpService", "StatusCode : " + ((HttpWebResponse)e.Response).StatusCode);
                    //Log.Error("HttpService", "StatusDescription : " + ((HttpWebResponse)e.Response).StatusDescription);
                //}
                //throw new WxPayException(e.ToString());
               
            }
            catch (Exception e)
            {
              
                //Log.Error("HttpService", e.ToString());
                //throw new WxPayException(e.ToString());
            }
            finally
            {
                //关闭连接和流
                if (response != null)
                {
                    response.Close();
                }
                if (request != null)
                {
                    request.Abort();
                }
            }
            return result;
        }