编辑代码

using System.IO;
using System.Text;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;

        private const String host = "https://ncovdata.market.alicloudapi.com";
        private const String path = "/ncov/cityDiseaseInfoWithTrend";
        private const String method = "GET";
        private const String appcode = "68029373a8a7400b98ed29a1597e1e79";

        static void Main(string[] args)
        {
            String querys = "";
            String bodys = "";
            String url = host + path;
            HttpWebRequest httpRequest = null;
            HttpWebResponse httpResponse = null;

            if (0 < querys.Length)
            {
                url = url + "?" + querys;
            }

            if (host.Contains("https://"))
            {
                ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);
                httpRequest = (HttpWebRequest)WebRequest.CreateDefault(new Uri(url));
            }
            else
            {
                httpRequest = (HttpWebRequest)WebRequest.Create(url);
            }
            httpRequest.Method = method;
            httpRequest.Headers.Add("Authorization", "APPCODE " + appcode);
            if (0 < bodys.Length)
            {
                byte[] data = Encoding.UTF8.GetBytes(bodys);
                using (Stream stream = httpRequest.GetRequestStream())
                {
                    stream.Write(data, 0, data.Length);
                }
            }
            try
            {
                httpResponse = (HttpWebResponse)httpRequest.GetResponse();
            }
            catch (WebException ex)
            {
                httpResponse = (HttpWebResponse)ex.Response;
            }

            Console.WriteLine(httpResponse.StatusCode);
            Console.WriteLine(httpResponse.Method);
            Console.WriteLine(httpResponse.Headers);
            Stream st = httpResponse.GetResponseStream();
            StreamReader reader = new StreamReader(st, Encoding.GetEncoding("utf-8"));
            Console.WriteLine(reader.ReadToEnd());
            Console.WriteLine("\n");

        }

        public static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
        {
            return true;
        }