控制台发起http请求

class Program
    {
        static string url = "http://localhost:56157/";  //接口地址
        static string method = string.Empty; //接口方法

        static void Main(string[] args)
        {
            string key = "T8951SLI02UTY983CVBAX03"; //接口的授权Key
            Dictionary<string, string> pars = new Dictionary<string, string>(); //参数

            //请求接口
            //  ①创建查询参数Json对象
            Console.WriteLine("创建接口查询参数...");
            var dataJson = JsonHelper.ObjectConvertJson(new { ID = "10001" });
            //  ②获取此次请求签名
            Console.WriteLine("开始获取签名...");
            CommResponse<string> sign = getApiSign("Query", dataJson);
            if (sign.Code == 1)
            {
                Console.WriteLine("签名获取成功：" + sign.Data);
                //获取签名成功则继续请求数据接口
                //  ③创建签名Json
                var signJson = JsonHelper.ObjectConvertJson(new { Key = key, Sign = sign.Data, Type = "Query" });
                //  ④封装参数开始请求
                pars.Add("param", signJson);
                pars.Add("json", dataJson);
                method = "queryUser";
                Console.WriteLine("开始发起查询请求...");
                string result = Http.SendRequest(url + method, pars);

                Console.WriteLine("请求结果：" + result);
            }
            else
            {
                //获取签名失败
                Console.WriteLine("签名获取失败：" + sign.Message);
            }


            Console.ReadKey();
        }

        /// <summary>
        /// 获取请求签名
        /// </summary>
        /// <param name="type">操作类型</param>
        /// <param name="data">要请求的数据</param>
        /// <returns></returns>
        public static CommResponse<string> getApiSign(string type, string data)
        {
            Dictionary<string, string> pars = new Dictionary<string, string>(); //参数
            string key = "T8951SLI02UTY983CVBAX03"; //接口的授权Key
            method = "getSign";
            pars.Add("key", key);
            pars.Add("type", type);
            pars.Add("data", data);
            string result = Http.SendRequest(url + method, pars);
            if (!string.IsNullOrWhiteSpace(result))
            {
                return JsonHelper.JsonConvertObject<CommResponse<string>>(result);
            }
            else
            {
                return new CommResponse<string>() { Code = 2, Message = "获取失败" };
            }
        }
    }

http帮助类：

public class Http
    {
        /// <summary>
        /// 发起请求
        /// </summary>
        /// <param name="url">接口地址</param>
        /// <param name="pars">字典类型的参数集合</param>
        /// <param name="timeout"></param>
        /// <returns></returns>
        public static string SendRequest(string url, IDictionary<string, string> pars, int timeout = 120)
        {
            HttpWebRequest request = CreateRequest(url);

            byte[] pdata = Encoding.UTF8.GetBytes(BuildQuery(pars, "utf-8"));

            request.ContentLength = pdata.Length;

            Stream writer = null;
            try
            {
                writer = request.GetRequestStream();
            }
            catch (Exception ex)
            {
                return ex.Message;
            }

            writer.Write(pdata, 0, pdata.Length);
            writer.Close();

            HttpWebResponse response = null;
            try
            {
                //获得响应流
                response = (HttpWebResponse)request.GetResponse();
            }
            catch (Exception ex)
            {
                return ex.Message;
            }
            StreamReader sRead = new StreamReader(response.GetResponseStream());

            string postContent = sRead.ReadToEnd();
            sRead.Close();

            return postContent;
        }


        /// <summary>
        /// 创建一个Http请求
        /// </summary>
        /// <param name="url">接口地址</param>
        /// <param name="timeout">超时时间:秒</param>
        /// <returns></returns>
        public static HttpWebRequest CreateRequest(string url, int timeout = 30)
        {
            HttpWebRequest mRequest = (HttpWebRequest)WebRequest.Create(url);

            mRequest.Proxy = null;
            mRequest.UseDefaultCredentials = false;
            mRequest.AllowWriteStreamBuffering = true;
            mRequest.Headers[HttpRequestHeader.AcceptLanguage] = "zh-CN";
            mRequest.Headers[HttpRequestHeader.AcceptEncoding] = "gzip, deflate";
            mRequest.Headers[HttpRequestHeader.CacheControl] = "no-cache";
            mRequest.Accept = "*/*";
            mRequest.Method = "POST";
            mRequest.ContentType = "application/x-www-form-urlencoded; charset=utf-8";
            mRequest.ProtocolVersion = HttpVersion.Version11;
            mRequest.ServicePoint.Expect100Continue = false;
            mRequest.ServicePoint.ConnectionLimit = 20000;
            mRequest.ServicePoint.MaxIdleTime = 20000;
            mRequest.ServicePoint.ReceiveBufferSize = 16384;
            mRequest.PreAuthenticate = true;
            mRequest.AllowAutoRedirect = false;
            mRequest.Timeout = timeout * 1000;
            mRequest.ReadWriteTimeout = timeout * 1000;
            mRequest.KeepAlive = true;
            return mRequest;
        }

        /// <summary>
        /// 组装普通文本请求参数。
        /// </summary>
        /// <param name="parameters">Key-Value形式请求参数字典</param>
        /// <returns>URL编码后的请求数据</returns>
        static string BuildQuery(IDictionary<string, string> parameters, string encode)
        {
            StringBuilder postData = new StringBuilder();
            bool hasParam = false;
            IEnumerator<KeyValuePair<string, string>> dem = parameters.GetEnumerator();
            while (dem.MoveNext())
            {
                string name = dem.Current.Key;
                string value = dem.Current.Value;
                // 忽略参数名或参数值为空的参数
                if (!string.IsNullOrEmpty(name))
                {
                    if (hasParam)
                    {
                        postData.Append("&");
                    }
                    postData.Append(name);
                    postData.Append("=");
                    if (encode == "gb2312")
                    {
                        postData.Append(System.Web.HttpUtility.UrlEncode(value, Encoding.GetEncoding("gb2312")));
                    }
                    else if (encode == "utf8")
                    {
                        postData.Append(System.Web.HttpUtility.UrlEncode(value, Encoding.UTF8));
                    }
                    else
                    {
                        postData.Append(value);
                    }
                    hasParam = true;
                }
            }
            return postData.ToString();
        }
    }

--来源：C# Nancy框架开发 WebApi 二：接口安全签名认证 - 阿东呢 - 博客园 (cnblogs.com)