How to get value of textbox in React?
<p>I just started using React.js, and I'm just not sure whether there is a special way to get the value of a textbox, returned in a component like this:</p>

<pre><code>var LoginUsername = React.createClass({
  render: function () {
    return (
      &lt;input type="text" autofocus="autofocus" onChange={this.handleChange} /&gt;
    )
  },
  handleChange: function (evt) {
    this.setState({ value: evt.target.value.substr(0, 100) });
  }
});
</code></pre>