javascript - 为什么 setState throw 对象作为 React 子对象无效？

Question

尝试使用 this.setState(...) 时出现错误

  state = {
    results: {},
    isFinished: false,
    activeQuestion: 0,
    answerState: null,
    quiz: [],
    loading: true
  };

  async componentDidMount() {
    try {
      const resp = await axios.get(`/quizes/${this.props.match.params.id}.json`);
      const quiz = resp.data;
      this.setState({
        quiz,
        loading: false
      })
    } catch (e) {
      console.log(e);
    }
  }

我的服务器请求成功返回一个数组，但是当我试图将它的值设置为本地状态时我得到了错误:

Objects are not valid as a React child (found: object with keys {errorMessage, label, touched, valid, validation, value}). If you meant to render a collection of children, use an array instead. in span (at ActiveQuiz.js:9) in p (at ActiveQuiz.js:8) in div (at ActiveQuiz.js:7) in ActiveQuiz (at Quiz.js:109) in div (at Quiz.js:98) in div (at Quiz.js:97) in Quiz (created by Route) in Route (at App.js:16) in Switch (at App.js:13) in main (at Layout.js:37) in div (at Layout.js:24) in Layout (at App.js:12) in App (at src/index.js:10) in Router (created by BrowserRouter) in Brodetailuter (at src/index.js:9)

和细节:

  21 | const resp = await axios.get(`/quizes/${this.props.match.params.id}.json`);   
  22 | const quiz = resp.data;   
  23 | 
> 24 | this.setState({   
  25 |   quiz,   
  26 |   loading: false   
  27 | })

如果我记录 quiz 对象，我会在控制台中得到 [{}]。并且所有的底层组件都成功获得了 props。

  render() {
    return (
      <div className={classes.Quiz}>
        <div className={classes.QuizWrapper}>
          <h1>Please answere:</h1>
          {
            this.state.loading
              ? <Loader/>
              : this.state.isFinished
              ? <FinishedQuiz
                results={this.state.results}
                quiz={this.state.quiz}
                onRetry={this.onRetryHandler}
              />
              : <ActiveQuiz
                answers={this.state.quiz[this.state.activeQuestion].answers}
                question={this.state.quiz[this.state.activeQuestion].question}
                onAnswerClick={this.onAnswerClickHandler}
                quizLength={this.state.quiz.length}
                answerNumber={this.state.activeQuestion + 1}
                state={this.state.answerState}
              />
          }
        </div>
      </div>
    )
  }

我用调试器 Prop 检查了 ActiveQuiz 是否正确。

请帮我解决一下。为什么会发生这种情况以及如何解决？

更新 1

const ActiveQuiz = props => {
  debugger
  return (
    <div className={classes.ActiveQuiz}>
      <p className={classes.Question}>
      <span>
        <strong>{props.answerNumber}.</strong>&nbsp;
        {props.question}
      </span>

        <small>{props.answerNumber} из { props.quizLength }</small>
      </p>

      <AnswersList
        state={props.state}
        answers={props.answers}
        onAnswerClick={props.onAnswerClick}
      />
    </div>
  )
};

Answer 1

您的错误表明它遇到了一个对象，因此无法呈现输出。它还指出，错误发生在 <span> 行.由于您的 activeQuestion是一个 int .因此你的 answerNumber Prop 不应该有错。

我的猜测是，它与您的 props.question 的数据结构有关.也许您要渲染的是一个对象/嵌套对象，因此会抛出一个错误，表明它无效。

希望对您有所帮助:)