如何使用基本授权发布REST api请求

Question

我刚刚在Visual Studio 2015中创建了一个新的C＃项目，我运行了该项目，但最终出现错误。

此请求的授权已被拒绝。

但是它给邮递员带来了预期的结果

这是我的代码

            var httpWebRequest = (HttpWebRequest)WebRequest.Create(@"https://uatweb.sampath.lk/webservicesRest/api/lankabell/recoverycalling/v1/getrecoveryaccount");
            httpWebRequest.ContentType = "application/json";
            httpWebRequest.Headers.Add("ServiceName", "GetRecoveryAccountForLankabell");
            httpWebRequest.Headers.Add("TockenID", "0");
            httpWebRequest.Method = "POST";
            httpWebRequest.Headers["Authorization"] = "Basic " + Convert.ToBase64String(Encoding.UTF8.GetBytes(username + ":" + password));

            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;

            using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
            {

                var bodydata = new BodyData { userid = "RANIL", RequestTime = DateTime.Now.ToString()};

                string json = JsonConvert.SerializeObject(bodydata);

                streamWriter.Write(json);
                streamWriter.Flush();
                streamWriter.Close();

                try
                {
                    var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();

                    using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
                    {

                        responce = streamReader.ReadToEnd();

                    }
                }
                catch (WebException ex)
                {
                    var pageContent = new StreamReader(ex.Response.GetResponseStream())
                            .ReadToEnd();
                }
            }