Interactive Component With State

interactive-component-with-state.js

var StateExample = React.createClass({
  render: function() {
    getInitialState: function() {
      return {
        likes: 3
      }
    },
    increment: function(e) {
      this.setState({ likes: this.state.likes + 1 });
    },
    return (
      <p>
        {this.state.likes} people like this.
        <button onClick={this.increment}></button>
      </p>
    );
  }
});

See the tutorial at: http://www.uxnjs.com/how-to-update-state-in-react/