private async Task <SMTPResponse> _readResponseAsync()
        {
            var response = await _receiceRespone.Task;

            _lastResponse   = response;
            _receiceRespone = new TaskCompletionSource <SMTPResponse>();

            return(response);
        }
 protected SMTPUnexpectedReplyException(SerializationInfo info, StreamingContext context) : base(info, context)
 {
     Response = (SMTPResponse)info.GetValue(nameof(Response), typeof(SMTPResponse));
 }
 public SMTPUnexpectedReplyException(string message, SMTPResponse response) : base(message)
 {
     this.Response = response;
 }