Vue 测试实例 - 小库网

<script src="https://cdn.staticfile.net/vue/3.2.36/vue.global.min.js"></script>

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<div id = "app">

    <p style = "font-size:25px;">计数器: {{ counter }}</p>

    <button @click = "counter++" style = "font-size:25px;">点我</button>

</div>

<script>

const app = {

  data() {

    return {

      counter: 1

    }

  }

}

vm = Vue.createApp(app).mount('#app')

vm.$watch('counter', function(nval, oval) {

    alert('计数器值的变化 :' + oval + ' 变为 ' + nval + '!');

});

</script>

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