[react] react有几种构建组件的方式？可以写出来吗？

1.无状态函数式组件

function HelloComponent(props, /* context */) {
return <div>Hello {props.name}</div>
}
ReactDOM.render(<HelloComponent name="Sebastian" />, mountNode)

2.React.createClass

var InputControlES5 = React.createClass({
propTypes: {//定义传入props中的属性各种类型
initialValue: React.PropTypes.string
},
defaultProps: { //组件默认的props对象
initialValue: ''
},
// 设置 initial state
getInitialState: function() {//组件相关的状态对象
return {
text: this.props.initialValue || 'placeholder'
};
},
handleChange: function(event) {
this.setState({ //this represents react component instance
text: event.target.value
});
},
render: function() {
return (
<div>
Type something:
<input onChange={this.handleChange} value={this.state.text} />
</div>
);
}
});
InputControlES6.propTypes = {
initialValue: React.PropTypes.string
};
InputControlES6.defaultProps = {
initialValue: ''
};

3.React.Component

class InputControlES6 extends React.Component {
constructor(props) {
super(props);

// 设置 initial state
this.state = {
text: props.initialValue || 'placeholder'
};

// ES6 类中函数必须手动绑定
this.handleChange = this.handleChange.bind(this);
}

handleChange(event) {
this.setState({
text: event.target.value
});
}

render() {
return (
<div>
Type something:
<input onChange={this.handleChange}
value={this.state.text} />
</div>
);
}
}
InputControlES6.propTypes = {
initialValue: React.PropTypes.string
};
InputControlES6.defaultProps = {
initialValue: ''
};