Question

我想将我的“ componentDidMount”用作“ componentDidUpdate”。我希望能够填充

this.state.libelle_prerequis

喜欢

this.setState（{libelle_prerequis：this.state.donnees.libelle_prerequis }）;

donnes = {id：1，libelle_prerequis：“ dde”}

  constructor(props) {
    super(props);
    this.state = {
      donnees: '',
      libelle_prerequis: '',
      error: '',
    };
  }

  componentDidUpdate(prevsProp) {
    if (prevsProp.store !== this.props.store) {
      this.setState({
        donnees: this.props.store.libellesprerequis.find((p) => p.id == this.props.libelleprerequis.match.params.id),
      });
      this.setState({ libelle_prerequis: this.state.donnees.libelle_prerequis });
    }
  }

  componentDidMount() {
    this.setState(() => ({
      donnees: this.props.store.libellesprerequis.find((p) => p.id == this.props.libelleprerequis.match.params.id),
    }));
  }

  render() {
    <input
      className="form-control"
      type="text"
      placeholder="Libellé"
      autoFocus
      value={this.state.libelle_prerequis ? this.state.donnees.libelle_prerequis : ''}
      onChange={this.onLibellePrerequisChange}
    />;
  }

Answer 1

您可以执行以下操作：

 getDonnees = () => {
  const { store, libelleprerequis } = this.props;
  return store.libellesprerequis.find((p) => p.id == libelleprerequis.match.params.id);
}

componentDidUpdate(prevsProp) {
  if (prevsProp.store !== this.props.store) {
    const donnees = this.getDonnees();
    this.setState({
      donnees,
      libelle_prerequis: donness ? donnees.libelle_prerequis : ''
    });
  }
}

componentDidMount() {
  const donnees = this.getDonnees()
  this.setState({
    donnees
  });
}

您还可以添加检查以查看是否找到了donnees。假设donness是一个常量，其值将不会被更改。

问题componentDidMount设置状态如DidUpdate

1 个答案: