example 3 for react best practice to handle this

Hello.js

class Hello extends Components {
  constructor(props) {
    super(props);
    this.state = { message: "Hello" };
    this.logMessage = this.logMessage.bind(this); 
  }
  logMessage() {
    const { message } = this.state;
    console.log(message);
  }
  render() {
    return (
      <input type="button" value="Log" onClick={this.logMessage} />
    );
  }
}