React高阶组件

1、React高阶组件

function logHoc(WrappedComponent) {
  return class extends React.Component {
    constructor(props) {
      super(props);
    }
    componentWillMount() {
      this.start = Date.now();
    }
    componentDidMount() {
      this.end = Date.now();
      console.log(`渲染时间：${this.end - this.start} ms`);
    }
    componentWillUnmount() {}
    render() {
      console.log(this.props);
      return (
        <div>
          <div className="title">{this.props.loading ? 1 : 2}</div>
          <WrappedComponent {...this.props} />
        </div>
      );
    }
  };
}

export default React.memo(logHoc(TopSearch));