javascript - 更新 React Js 中的对象数组

Question

我想在 onChange 事件上更新问题名称。但问题是如果我只改变一个问题，每个问题都会改变。如何解决它？

class QuestionCreate extends React.Component {
    constructor(props){
        super(props);
        this.state = {
            datas: [],
            default_question: {
                isNew: true,
                question: {
                    name: 'Click to write the question text',
                    answer_options: [
                        {name: 'click to write choice 1', 'choice': true},
                        {name: 'click to write choice 1', 'choice': true},
                        {name: 'click to write choice 1', 'choice': true},
                    ]
                }
            }
        }

    }


    onChangeQuestion(qustions, index, event){
        let all_data = this.state.datas;
        let currentQuestion = all_data[index].question
        all_data[index]['question']['name'] = event.target.value;
        console.log(all_data[index]['question']['name'])
        this.setState({datas: all_data})

    }

    displayRow(){
    let rowData = this.state.datas.map( (data, index) =>{
        console.log("this is data:", data, index);
        return(
            <div className="well" key={ index }>
                <h3>Q. <input type="text" onChange={ this.onChangeQuestion.bind(this, data, index) } value={ data.question.name } /></h3>
                    <ul>
                        <li>option</li>
                    </ul>
            </div>
        )
    })

    return rowData;
}

Answer 1

您正在直接改变您的状态。

let all_data = this.state.datas;
let currentQuestion = all_data[index].question
all_data[index]['question']['name'] = event.target.value;

用途:

let all_data = JSON.parse(JSON.stringify(this.state.datas));
let currentQuestion = all_data[index].question;
all_data[index]['question']['name'] = event.target.value;
this.setState({datas: all_data});

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