Simple async HttpListener implementation.

SimpleAsyncHost.cs

 public class SimpleAsyncHost
    {
        private HttpListener _httpListener;
        private bool _stop;

        public SimpleAsyncHost()
        {
            _httpListener = new HttpListener();
            _httpListener.Prefixes.Add("http://localhost:10090/");

        }

        public void Stop()
        {
            _stop = true;
            _httpListener.Stop();
        }

        public async void ListenAsync()
        {
            _httpListener.Start();

            while (!_stop)
            {
                HttpListenerContext ctx = null;
                try
                {
                    ctx = await _httpListener.GetContextAsync();
                }
                catch (HttpListenerException ex)
                {
                    if (ex.ErrorCode == 995) return;
                }
                
                if(ctx == null) continue;
                
                //got a request
                string json = @"{ ""hello"": ""world"" }";
                var response = ctx.Response;
                response.Headers.Add(HttpResponseHeader.CacheControl, "private, no-store");
                response.ContentType = "text/plain";
                response.StatusCode = (int) HttpStatusCode.OK;

                var messageBytes = Encoding.UTF8.GetBytes(json);
                response.ContentLength64 = messageBytes.Length;
                await response.OutputStream.WriteAsync(messageBytes, 0, messageBytes.Length);
                response.OutputStream.Close();
                response.Close();
            }
        }
    }