react學習筆記3

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      <div id="demo"></div>        <script type="text/babel">            var ItemComponent = React.createClass({                render:function (){                    return (                        <li>{this.props.item}</li>                    )                    }            });                        var ListComponent = React.createClass({                render:function (){                    return (                        <ul>                            {                                this.props.listArr.map(function (item,index){                                    return <ItemComponent key={index} item={item} />                                })                            }                        </ul>                    )                    }            });            var FirstComponent = React.createClass({                    mixins:[React.addons.LinkedStateMixin],                    getInitialState:function (){                        return {                            mes:this.props.value,                            listArr:this.props.listArr                        }                        },                    render:function (){                        return (                            <div>                                <h1>{this.props.title}</h1>                                <input type="text" ref="text_input" valueLink={this.linkState("mes")} />/*引入react-with-addons庫,並配置mixins:[React.addons.LinkedStateMixin]後,可以使用linkState,類似雙向資料繫結,其實本質是內部實現了onChange事件*/                                /*ref屬性可以使當前元素通過this.refs.text_input找到*/                                <input type="button" onClick={this.addItemHandle} value={this.props.sendName} />                                /*this指向問題,沒搞懂*/                                <p>{this.state.mes}</p>                                <ListComponent listArr = {this.state.listArr}/>

/*這裡用this.state.listArr,而不用this.props.listArr,是因為state可變,要向子組件傳遞改變後的值*/                            </div>                        )                    },                    addItemHandle:function (){                        var value = this.refs.text_input.value;                        var newArr = this.state.listArr.concat([value])                        this.setState({listArr:newArr})                    }                });            var obj = {                title:‘react‘,                sendName:‘提交‘,                value:"請輸入留言",                listArr:[1,2,3,4,5,6,7,8]            }                        ReactDOM.render(                <FirstComponent {...obj} />,                document.getElementById("demo"),                function(){                    console.log("頁面渲染完成");                }            );/*JSX裡面不要寫分號,會報錯*//*class是關鍵字,要寫成className*//*設定樣式時,要寫成sytle={xx:xxx}的形式*/        </script>

 

react學習筆記3