Edit in JSFiddle

var PersonForm = React.createClass({
  render() {
    return <form onSubmit={this.handleSubmit}>
    	<div>
      	<label htmlFor="name"/>
      	<input type="text" name="name" value={this.state.name} onChange={this.bindState('name')} />
      </div>
      <div>
      	<label htmlFor="age"/>
      	<input type="number" name="age" value={this.state.age} onChange={this.bindState('age')}/>
      </div>
    	<div><input type="submit" value="Save"/></div>    
    </form>;
  },
  getInitialState() {
  	return this.props.person;
  },
  bindState(property) {
  	return (event) => { this.setState({ [property]: event.target.value }); };
  },
  handleSubmit(event) {
  	event.preventDefault();
  	console.log(this.state);
  }
});

var data = {name:"Eugene",age:46};

ReactDOM.render(
  <PersonForm person={data} />,
  document.getElementById('container')
);