QuickBooksService.cs

public void GetName(){
  try
            {
                var myQb = MyQb();
                if (myQb != null)
                {
                    TimeSpan retryInterval = new TimeSpan(0, 0, 0, 1);// To give a time interval of 1 second

                    QbTokenDto token = JsonConvert.DeserializeObject<QbTokenDto>(myQb.Settings);
                    OAuthRequestValidator oauthValidator = new OAuthRequestValidator(token.Token, token.TokenSecret, ConsumerKey, ConsumerSecret);
                    ServiceContext context = new ServiceContext(AppToken, token.Realm, IntuitServicesType.QBO, oauthValidator);
                    context.IppConfiguration.MinorVersion.Qbo = "5";
                    context.IppConfiguration.BaseUrl.Qbo = "https://sandbox-quickbooks.api.intuit.com/";
                    context.IppConfiguration.Message.Request.SerializationFormat = SerializationFormat.Json;
                    context.IppConfiguration.Message.Response.SerializationFormat = SerializationFormat.Json;
                    context.IppConfiguration.Message.Request.CompressionFormat = CompressionFormat.GZip;
                    context.IppConfiguration.Message.Response.CompressionFormat = CompressionFormat.GZip;
                    context.IppConfiguration.RetryPolicy = new Intuit.Ipp.Retry.IntuitRetryPolicy(5, retryInterval);

                    DataService service = new DataService(context);

                    Customer customer = new Customer()
                    {
                        Id = "59"
                    };
                    Customer resC = service.FindById(customer) as Customer;

                    var mess = resC.DisplayName;

                }
            }
            catch (IdsException exception)
            {
                var mess = exception.Message;   
                throw;
            }
           
        }
}