private bool IsClientInDatabase() { var clientRequest = new ClientRequest(); var responseData = clientRequest.Get(firstNameTextBox.Text, lastNameTextBox.Text, phoneNumberTextBox.Text, new DateTime(Convert.ToInt32(yearTextBox.Text), Convert.ToInt32(monthTextBox.Text), Convert.ToInt32(dayTextBox.Text))); //get client from database that has the same data as provided if (responseData != null) { return(true); } else { return(false); } }