<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>事件处理once修饰符</title>
    <style type="text/css">
        div>div{
            border: 1px solid black;
        }
        #outer{
            width: 200px;
            height: 200px;
            background-color: #bbbbbb;
        }
        #inner{
            width: 100px;
            height: 100px;
            background-color: #bc806b;
        }
    </style>
</head>
<body>
    <div id="app">
        <div id="outer" v-on:click.once="show('外层div被单击')">
            <div id="inner" v-on:click="show('内层div被单击')"></div>
        </div>
    </div>

    <script src="../js/vue.js"></script>

    <script>
        let vm = new Vue({
            el:'#app',
            methods:{
                show(message){
                    alert(message);
                }
            }
        });
    </script>
</body>
</html>