ControlledFormInput.component.js

class ControlledFormInput extends React.Component {
  constructor(props) {
    super(props);
    this.handleChange = this.handleChange.bind(this);
    this.state = { value: "Glad" };
  }
    
  handleChange(evt) {
    this.setState({ value: evt.target.value });
  }
  
  render() {
    return (
      <div>
        <h1>Hello {this.state.value}!</h1>
        <input type="text" value={this.state.value} onChange={this.handleChange} placeholder="Enter your name" />
      </div>
    )
  }
}