如何访问组件状态内容?

时间:2018-12-26 21:41:08

标签: reactjs

我正在使用React Slick库来创建轮播组件。在构造函数中,我定义以下状态:

class ArticlesContainer extends Component {
  constructor(props) {
    super(props);

    this.state = {
      lists: [],
      settings: {
        dots: true,
        infinite: false,
        speed: 500,
        arrows: true,
        slidesToShow: 1,
        slidesToScroll: 1,
      },
    };
  }
}

在发生事件后,我这样称呼this.setState:

this.setState(prevState => ({
  lists: response.data,
  settings: {
    ...prevState.settings,
    customPaging: function(i) {
      console.log(this.state.lists);

      return <a>{i}</a>;
    },
  },
}));

问题在于,当我致电console.log(this.state.lists)时,它表示未定义。如何从customPaging访问组件的list属性?

1 个答案:

答案 0 :(得分:0)

考虑将customPaging回调修改为箭头函数,而不是“常规函数”:

this.setState(prevState => ({
  lists: response.data,
  settings: {
    ...prevState.settings,
    customPaging: (i) => {

      // "this" will now correspond to the component instance
      // meaning that this.state will be the current state of
      // your outer ArticlesContainer component
      console.log(this.state.lists);

      return <a>{i}</a>;
    },
  },
}));

这将导致customPaging回调的上下文是您组件的上下文,从而使您可以访问state.lists组件实例的<ArticlesContainer />数组。