在React中,我正在创建一个选择题调查表。将生成带有可能答案的复选框。当用户勾选答案并重新加载页面时,所选答案的复选框不会保留其选中状态。
问题和答案在第一次加载时作为对象数组从数据库中获取。用户可以在一个问题的多个复选框中打勾。创建第二个数组,其中包含用户选择并发送到数据库的所有多个答案都有对象。重新加载时,此第二个数组将与第一个数组一起添加到组件的状态。
const Checkbox = ({ id, name, options, onChange }) => {
return (
<div className="checkbox-group">
{options.map((option, index) => {
<div key={index}>
<label htmlFor={id}>
<input
type="checkbox"
name={name}
id={id}
value={option}
onChange={onChange}
/>
{option}
</label>
</div>
}
</div>
);
}
class Form extends Component {
constructor(props) {
super(props);
this.state = {
questionnaire: [],
answeredQuestions: [],
formData: {},
};
this.handleChange = this.handleChange.bind(this);
}
async componentDidMount() {
// it doesn't matter how I fetch the data, could have been axios, etc...
let questionnaire = await fetch(questionnaireUrl);
let answeredQuestions = await fetch(answeredQuestionsUrl);
this.setState({ questionnaire, answeredQuestions });
}
render() {
return (
<div className="questionnaire-panel">
<h1>Quiz</h1>
{this.state.questionnaire.map((question, index) => {
return (
<div key={index}>
<Checkbox
options={questions.answers}
checked={// this where I'm stuck on what to do}
name="the-quiz"
id={`the-quiz_num_${index + 1}`}
onChange={this.handleChange}
/>
</div>
)
})}
</div>
);
}
handleChange(event) {
let target = event.target;
let value = target.value;
let name = target.name;
let chosenAnwersArray = [];
let chosenAnswer = {
answer: value,
checked: true,
};
if (this.state.questionnaire.includes(chosenAnswer)) {
newChosenAnwersArray = this.state.questionnaire.filter(q => {
return q.answer !== chosenAnswer.answer;
});
} else {
newChosenAnwersArray = [...newChosenAnwersArray, chosenAnswer];
}
this.setState(prevState => ({
formData: {
[name]: value,
},
answeredQuestions: newChosenAnwersArray
}));
}
}
我想比较this.state
中的这2个数组,如果array2中的答案在array1中,则选中相应的复选框。有没有更好的方法,请教我!