在Botframework V4中扩展和链接对话框的正确方法？

public class MainDialog : WaterfallDialog
{
    public MainDialog(string dialogId, IEnumerable<WaterfallStep> steps)
        : base(dialogId, steps)
    {
        AddStep(Step1Async);
        AddStep(Step2Async);
        AddStep(Step3Async);
    }

    private async Task<DialogTurnResult> Step1Async(WaterfallStepContext stepContext, CancellationToken cancellationToken)
    {
        await stepContext.Context.SendActivityAsync("Step 1");

        // 调用ComponentDialog中的对话框
        return await stepContext.BeginDialogAsync("ComponentDialogId");
    }

    private async Task<DialogTurnResult> Step2Async(WaterfallStepContext stepContext, CancellationToken cancellationToken)
    {
        await stepContext.Context.SendActivityAsync("Step 2");

        // 继续下一个对话步骤
        return await stepContext.NextAsync();
    }

    private async Task<DialogTurnResult> Step3Async(WaterfallStepContext stepContext, CancellationToken cancellationToken)
    {
        await stepContext.Context.SendActivityAsync("Step 3");

        // 结束对话
        return await stepContext.EndDialogAsync();
    }
}

public class ComponentDialog : ComponentDialog
{
    public ComponentDialog(string dialogId)
        : base(dialogId)
    {
        AddDialog(new TextPrompt("textPrompt"));

        // 添加其他对话框组件
        AddDialog(new OtherDialog("otherDialogId"));

        AddDialog(new WaterfallDialog("componentWaterfall", new WaterfallStep[]
        {
            Step1Async,
            Step2Async,
        }));
    }

    private async Task<DialogTurnResult> Step1Async(WaterfallStepContext stepContext, CancellationToken cancellationToken)
    {
        await stepContext.Context.SendActivityAsync("Component Step 1");

        // 调用其他对话框组件
        return await stepContext.BeginDialogAsync("otherDialogId");
    }

    private async Task<DialogTurnResult> Step2Async(WaterfallStepContext stepContext, CancellationToken cancellationToken)
    {
        await stepContext.Context.SendActivityAsync("Component Step 2");

        // 结束对话框组件并返回结果
        return await stepContext.EndDialogAsync();
    }
}

// 在Bot中使用对话框
public class MyBot : ActivityHandler
{
    private DialogSet _dialogSet;
    private MainDialog _mainDialog;

    public MyBot()
    {
        _mainDialog = new MainDialog("mainDialog", new WaterfallStep[]
        {
            StepAsync,
        });

        _dialogSet = new DialogSet();
        _dialogSet.Add(_mainDialog);
    }

    protected override async Task OnMessageActivityAsync(ITurnContext<IMessageActivity> turnContext, CancellationToken cancellationToken)
    {
        var dialogContext = await _dialogSet.CreateContextAsync(turnContext, cancellationToken);
        var results = await dialogContext.ContinueDialogAsync(cancellationToken);

        if (results.Status == DialogTurnStatus.Empty)
        {
            await dialogContext.BeginDialogAsync("mainDialog", cancellationToken: cancellationToken);
        }
    }

    private async Task<DialogTurnResult> StepAsync(WaterfallStepContext stepContext, CancellationToken cancellationToken)
    {
        await stepContext.Context.SendActivityAsync("Main Step");

        // 继续下一个对话步骤
        return await stepContext.NextAsync();
    }
}