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How to access the refs of children in a parent to do something with them in the parent function?

class Parent extends Component {

  someFunction(){
  // how to access h1 element of child in here ??
  }

  render() {
    return (
      <Child />
    );
  }
}



class Child extends Component {
  render() {
    return (
      <h1 ref="hello">Hello</h1>
    );
  }
}

How to access the refs of children in a parent to do something with them in the parent function?

class Parent extends Component {

  someFunction(){
  // how to access h1 element of child in here ??
  }

  render() {
    return (
      <Child />
    );
  }
}



class Child extends Component {
  render() {
    return (
      <h1 ref="hello">Hello</h1>
    );
  }
}

• javascript
• reactjs
• react-native

Share Improve this question Follow edited Jul 17, 2019 at 1:31 shriek 5,85388 gold badges5252 silver badges8383 bronze badges asked Mar 10, 2017 at 6:29 Amit MAmit M 5111 gold badge11 silver badge33 bronze badges 1

• the second line of the question is actually first line of the code . cant format that because of this stupid checks this website has in place – Amit M Commented Mar 10, 2017 at 6:39

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 5

To add to Shubham's answer, the child refs have to be accessed inside of ponentDidMount() inside parent. Something like:

class Parent extends React.Component {
    ponentDidMount(){
        var elem1 = this.refs.child1.refs.childRefName;
    }

    return (
    <View>
      <Child1 ref='child1'/>
      <Child2 />
      <Child3 />
    </View>
    );
}

You can access the child refs by providing a ref to the child element and accessing it like ReactDOM.findDOMNode(this.refs.child.refs.hello)

In your case the child ponent doesn't begin with Uppercase letter which you need to change.

class App extends React.Component {
   ponentDidMount() {
       console.log(ReactDOM.findDOMNode(this.refs.child.refs.hello));
   
   }
   render() {
      return (
        <Child ref="child"/>
      );
     }
    }
class Child extends React.Component {
     render() {
      return (
        <h1 ref="hello">Hello</h1>
      );
     }
    }
    
    
    ReactDOM.render(<App/>, document.getElementById('app'));

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

You can also use React.forwardingRef method to make the Child ponent able to receive and define a ref from its parent.

Here is the documentation for the method:

https://reactjs/docs/forwarding-refs.html

And here is an example of how you might implement it in your code:

const Child = React.forwardRef((_, ref) => (
  <h1 ref={ref}>Child Component</h1>
));

function Parent() {
  var h1 = React.createRef();

  React.useEffect(() => {
    console.log(h1.current);
  });

  return <Child ref={h1} />;
}

https://reactjs/docs/forwarding-refs.html

I hope it helps.

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