Can I add custom logic to a Bot Framework PromptDialog for handling invalid answers?

问题

In my Bot Framework project, I'm using a PromptDialog to show a predefined set of valid options, with the below code:

        var pickListOptions = new List<Option>();
        pickListOptions.AddRange(
            _currentQuestion.validValues.Select(x => Option.CreateOption(x)));

        PromptDialog.Choice(context, choiceSelected,
            pickListOptions,
            _currentQuestion.label,
             "Sorry, I didn't get that", 3, PromptStyle.Keyboard);

When a free-form answer is typed in which is not in the list of valid values is entered, the "Sorry, I didn't get that" message is automatically displayed and the question is reprompted. However, I want to potentially handle certain invalid answers with a different dialog (i.e. if the user is asking for help). Is there any way to override the automatic reprompt with custom logic?

回答1:

There are likely two valid answers for this question:

1. If you want to change the validation, you can inherit from the PromptChoice and override the TryParse or the MessageReceivedAsync methods. For example, the CancelablePromptChoice
2. For handling global commands, like help, instead of doing what I explained in #1, you might want to consider using Scorables. Take a look to the GlobalMessagesHandlers sample to understand more.

来源：https://stackoverflow.com/questions/44704544/can-i-add-custom-logic-to-a-bot-framework-promptdialog-for-handling-invalid-answ