Simple API client

simpleclient.cs

using System;
using System.IO;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;
using System.Runtime.Serialization.Json;

using Client.Entities;

namespace Client
{
    public class APIClient
    {
        public string RawData { get; set; }
        public string ClientID { get; set; }
        public string ClientSecret { get; set; }
        public string HostName { get; set; }

        public APIClient(string Host, string User, string Password)
        {
          HostName = Host;
          ClientID = User;
          ClientSecret = Password;
        }

        public async Task<string[]> PostContent(string Path, string JSONBody)
        {
            string[] result = new string[3];
            UriBuilder uri = new UriBuilder
            {
                Scheme = "https",
                Port = -1,
                Host = HostName,
                Path = Path
            };
            var byteArray = new System.Text.UTF8Encoding().GetBytes($"{ClientID}:{ClientSecret}");

            using (var client = new HttpClient())
            {
                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;
                client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", Convert.ToBase64String(byteArray));

                var response = await client.PostAsync(uri.ToString(), new StringContent(JSONBody, System.Text.Encoding.Unicode, "application/json"));

                if (response.IsSuccessStatusCode)
                {
                    RawData = response.Content.ReadAsStringAsync().Result;

                    using var ms = new MemoryStream(System.Text.Encoding.Unicode.GetBytes(RawData));
                    DataContractJsonSerializer ds = new DataContractJsonSerializer(typeof(PostResponse));
                    PostResponse presp = (PostResponse)ds.ReadObject(ms);
                    result[0] = presp.PO_DATA.BATCH_NUMBER;
                    result[1] = presp.PO_DATA.PO_HEADER.Count.ToString();
                    result[2] = presp.PO_DATA.CUSTOMER_NAME;
                }
                else
                {
                    result[0] = response.StatusCode.ToString();
                    result[1] = response.ReasonPhrase;
                    result[2] = "0";
                }
            }

            return result;
        }
    }
}