TypeError：無法讀取未定義React.js的屬性“字段”

Question

我建立了一個聊天機器人，但與Bot的對話有些問題。 在對話的某個時刻，我看到了錯誤：TypeError：無法讀取未定義的屬性“ fields”

I building a chatbot and I have some problem with the conversation with the Bot. At some point of the conversation I saw error: TypeError: Cannot read property 'fields' of undefined



componentDidUpdate() {
        this.scrollToBottom();
        if ( this.talkInput ) {
            this.talkInput.focus();
        }
    }
    _handleInputKeyPress(e) {
        if (e.key === 'Enter') {
            this.df_text_query(e.target.value);
            e.target.value = '';
        }
    }

    _handleQuickReplyPayload(payload, text) {
        switch (payload) {
            case 'recommend_yes':
                this.df_event_query('SHOW_RECOMMENDATIONS');
                break;
            case 'training_maybe':
                this.df_event_query(text);
                break;
            default:
                this.df_text_query(text);
        }
    }

    renderCards(cards) {
        return cards.map((card, i) => <Card key={i} payload={card.structValue}/>);
    }
    renderOneMessage(message, i) {
        if (message.msg && message.msg.text && message.msg.text.text) {
            return <Message key={i} speaks={message.speaks} text={message.msg.text.text}/>; 
        } else if (message.msg && message.msg.payload.fields.cards) { //message.msg.payload.fields.cards.listValue.values
            return <div key={i}>
                <div className="card-panel grey lighten-5 z-depth-1">
                    <div style={{overflow: 'hidden'}}>
                        <div className="col s2">
                            <a href="/" className="btn-floating btn-large waves-effect waves-light red">{message.speaks}</a>
                        </div>
                        <div style={{ overflow: 'auto', overflowY: 'scroll'}}>
                            <div style={{ height: 300, width:message.msg.payload.fields.cards.listValue.values.length * 270}}>
                                {this.renderCards(message.msg.payload.fields.cards.listValue.values)}
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        } else if (message.msg &&
            message.msg.payload &&
            message.msg.payload.fields &&
            message.msg.payload.fields.quick_replies
        ) {
            return <QuickReplies
                text={message.msg.payload.fields.text ? message.msg.payload.fields.text : null}
                key={i}
                replyClick={this._handleQuickReplyPayload}
                speaks={message.speaks}
                payload={message.msg.payload.fields.quick_replies.listValue.values}/>;
        }
    }
    renderMessages(returnedMessages) {
        if (returnedMessages) {
            return returnedMessages.map((message, i) => {
                    return this.renderOneMessage(message, i);
                }
            )
        } else {
            return null;
        }
    }

當我點擊按鈕“是”時，機器人需要給我一些答案。 但是相反，我在頁面上看到此錯誤： https : //prnt.sc/ox4i1r

Answer 1

您需要在此處添加額外的有效負載檢查：

} else if (message.msg && message.msg.payload.fields.cards) {

像這樣：

} else if (message.msg && message.msg.payload &&  message.msg.payload.fields.cards) {

Answer 2

'use strict';

const chatbot = require('../chatbot/chatbot');

module.exports = app => {

    app.get('/', (req, res) => {
    res.send({'zdravo': 'ljudi'})
    });

    app.post('/api/df_text_query', async (req, res) => {

        let responses = await chatbot.textQuery(req.body.text, req.body.userID, req.body.parameters);        
        res.send(responses[0].queryResult);
        res.end();
    });

    app.post('/api/df_event_query', async (req, res) => {
        let responses = await chatbot.eventQuery(req.body.event, req.body.userID, req.body.parameters);        
        res.send(responses[0].queryResult);
        res.end();
    });

}

這是帶有df_event_query的nodejs代碼