passing props from Child to Parent

propsToParent.js

class Parent extends React.Component {
	constructor(props) {
  	super(props);
    this.doSomething = this.doSomething.bind(this);
  }
  
  doSomething(value) {
  	// expecting value to be 'hello'
    // ...
  }
  
  render() {
  	return <Child valueHandler={this.doSomething} />;
  }
}

class Child extends React.Component {
	constructor(props) {
  	super(props);
  }
  
  sendToParent(value) {
  	// send value back up to parent
  	this.props.valueHandler(value);
  }
  
  // ...whatever else
}