class App extends React.Component {

  constructor(props) {

    super(props);

    this.state = {

      clicks: 0

    };

    this.click = this.click.bind(this);

    this.manyClicks = this.manyClicks.bind(this);

  }

  click() {

    this.setState({clicks: this.state.clicks + 1});

  }

  manyClicks() {

    var i = 0;

    for (i = 0; i < 100; i++) {

      this.click();

    }

  }

  render() {

    return (

      <div>

        <button onClick={this.click}>1 Click</button>

        <button onClick={this.manyClicks}>100 Clicks</button>

        <h3>{this.state.clicks}</h3>

      </div>

    );

  }

}

​

ReactDOM.render(<App />, document.getElementById('app'));