Testaccount
/
1.Test


			
				
					
						
						
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							<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <!-- 引入文件  *顺序不能改变-->
    <!-- 将jsx转为js -->
    <script src="./babel.min.js"></script>
    <!-- react核心库 -->
    <script src="./react.development.js"></script>
    <!-- react中的dom操作库 -->
    <script src="./react-dom.development.js"></script>
</head>

<body>
    <div id="root"></div>
    <script type="text/babel">
        // 类组件 state 可以修改数据
        // 计数器
        class HandleCount extends React.Component {
            // 定义初始数值
            state = {
                title: "计数器",
                count: 0,
            };
            // 数据更新视图未变
            //vue的解决方案：vue.set() 或 this.$set
            // react解决方案：
            handleAdd() {
                this.setState({
                    count:this.state.count + 1,
                });
            }
            handleReduce = ()=>{
                console.log(this)
                this.setState({
                    count:this.state.count -1,
                });
            }
            render() {
                return (
                    <div>
                        <h1>{this.state.title}</h1>
                        <p>当前数值：{this.state.count}</p>
                        <button onClick={this.handleAdd.bind(this)}>+</button>
                        <button onClick={this.handleReduce}>-</button>
                    </div>
                )
            }
        }
        let element = <HandleCount/>
        ReactDOM.createRoot(document.querySelector("#root")).render(element);
    </script>
</body>

</html>