React.js-如何将值从子组件传递到祖父母组件？

Question

以下是在reactjs中将值从子组件传递到父组件的正确示例。

App.jsx

import React from 'react';

class App extends React.Component {

   constructor(props) {
      super(props);

      this.state = {
         data: 'Initial data...'
      }

      this.updateState = this.updateState.bind(this);
   };

   updateState() {
      this.setState({data: 'Data updated from the child component...'})
   }

   render() {
      return (
         <div>
            <Content myDataProp = {this.state.data} 
               updateStateProp = {this.updateState}></Content>
         </div>
      );
   }
}

class Content extends React.Component {

   render() {
      return (
         <div>
            <button onClick = {this.props.updateStateProp}>CLICK</button>
            <h3>{this.props.myDataProp}</h3>
         </div>
      );
   }
}

export default App;

main.js

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.jsx';

ReactDOM.render(<App/>, document.getElementById('app'));

我需要明确有关将值从子组件传递到祖父母组件的概念。请帮我！！

Answer 1

您可以通过，将update函数传递给大子级props，只需从子组件中再次传递即可。

class App extends React.Component {

  constructor(props) {

    super(props)

    this.state = {

      data: 'Initial data...'

    }

    this.updateState = this.updateState.bind(this);

  }



  updateState(who) {

    this.setState({data: `Data updated from ${who}`})

  }



  render() {

    return (

      <div>

        Parent: {this.state.data}

        <Child update={this.updateState}/>

      </div>

    )

  }

}



class Child extends React.Component {

  render() {

    return (

      <div>

        Child component

        <button onClick={() => this.props.update('child')}>

          CLICK

        </button>

        <GrandChild update={this.props.update}/>

      </div>

    );

  }

}



class GrandChild extends React.Component {

  render() {

    return (

      <div>

        Grand child component

        <button onClick={() => this.props.update('grand child')}>

          CLICK

        </button>

      </div>

    );

  }

}

ReactDOM.render(<App />, document.getElementById('root'))


<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>

<div id="root"></div>