全域呼叫終斷原本的dialog流程，這個部份去年coding的時候，還沒有。

// The dialog stack is cleared and this dialog is invoked when the user enters 'help'.
bot.dialog('help', function (session, args, next) {
    session.endDialog("This is a bot that can help you make a dinner reservation. <br/>Please say 'next' to continue");
})
.triggerAction({
    matches: /^help$/i,
});

bot.dialog('help', function (session, args, next) {
    session.endDialog("This is a bot that can help you make a dinner reservation. <br/>Please say 'next' to continue");
})
.triggerAction({
    matches: /^help$/i,
    onSelectAction: (session, args, next) => {
        // Add the help dialog to the dialog stack 
        // (override the default behavior of replacing the stack)
        session.beginDialog(args.action, args);
    }
});

這兩個範例都可以全域呼叫，
差別在於 onSelectAction 不會終止原本的dialog流程，結束之後，還是會回到原本的dialog.