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HTML

              
                <div id="app"></div>
              
            
!

CSS

              
                
              
            
!

JS

              
                /*
 * 最上层Component
 */
class Components extends React.Component {
  
  constructor(props){
    super(props);
    this.state = {}
  }
  componentWillMount(){
    console.debug("实例化:componentWillMount")
  }
  componentDidMount(){
    console.debug("实例化:componentDidMount")
  }
  componentWillReceiveProps(){
    console.debug("存在期:componentWillReceiveProps")
  }
  shouldComponentUpdate(nextProps,nextState){
    console.debug("存在期:shouldComponentUpdate",nextProps,nextState)
    return true;
  }
  componentWillUpdate(){
    console.debug("存在期:componentWillUpdate")
  }
  componentDidUpdate(){
    console.debug("存在期:componentDidUpdate")
  }
  render() {
    if(!this.props.reRender){
      console.debug("实例化:render")
    }else{
      console.debug("存在期:render")
    }
    return (
      <div>
        <br />
        请查看下面的console
        <br />
      </div>
    )
      
  }
}
Components.defaultProps = {
    text: "hello word",
}
class App extends React.Component{
  constructor(props){
    super(props);
    this.state = {}
  }
  refresh(){
    return (e)=>{
      this.setState({
        reRender: true,
      })
    }
  }
  render(){
    return (
      <div>
        <Components reRender={this.state.reRender}/>  
        <button onClick={this.refresh()}>
            更新Component
        </button>
      </div>
    )
  }
}
//这个组件是没有调用的,但是,getDeafultProps直接执行了
var Test = React.createClass({
  getDefaultProps: function(){
    console.debug("Test组件为调用,直接执行了defaultProps")
    return {
      
    }
  },
  render(){
    return (
      <div></div>
    )
  },
})
/*
 * Render the above component into the div#app
 */
ReactDOM.render(<App />, document.getElementById('app'));
              
            
!
999px

Console