<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8"/>
        <script src="vue.js"></script>
    </head>
    <body>
        <div>
        <h1>--访问子组件或子元素--</h1>
        <div id="example1">
            <base-input></base-input>
        </div>
        <script>
        // 定义组件
        Vue.component('base-input', {
            methods: {
                add: function () {
                    this.$refs.usernameInput.value = "Hello";
                }
            },
            template: '\
                <div>\
                    <input type="text" value="Hi" ref="usernameInput"></input>\
                    <button v-on:click="add">添加</button>\
                </div>\
            '
        })
        // Vue 根实例
        var example1 = new Vue({
            el: '#example1',
        })
        </script>
        </div>
    </body>
</html>