toggle function react js

1class Toggle extends React.Component {
2  constructor(props) {
3    super(props);
4    this.state = {isToggleOn: true};
5
6    // This binding is necessary to make `this` work in the callback    this.handleClick = this.handleClick.bind(this);  }
7
8  handleClick() {    this.setState(state => ({      isToggleOn: !state.isToggleOn    }));  }
9  render() {
10    return (
11      <button onClick={this.handleClick}>        {this.state.isToggleOn ? 'ON' : 'OFF'}
12      </button>
13    );
14  }
15}
16
17ReactDOM.render(
18  <Toggle />,
19  document.getElementById('root')
20);