当this.props.children发生更改时，如何重新呈现组件

Below is my sample code

下面是我的示例代码

var Test = React.createClass({

componentDidMount: function(){
    //do something
}

render: function() {
    return (
        <div id="testDiv">
            <Header 
                messages={this.props.mesage} />
            {this.props.children}
            <Footer />
        </div>
    );
}
});
var Test