<body>
<div id="app">
<button @click="add">+</button>
<button @click="sub">-</button>
<p> {{ num }} </p>
</div>
<script src='https://cdn.jsdelivr.net/npm/vue@2.6.12/dist/vue.js'></script>
<script>
const app = new Vue({
el: '#app',
data: {
num: 0,
},
methods: {
add() { // 用ES6函数增强写法
this.num++;
},
sub() {
this.num--;
}
}
})
</script>
</body>