<template>
  <p id="app">
   <component :is="currentView"></component>
   <button @click="changeView('A')">切换到A</button>
   <button @click="changeView('B')">切换到B</button>
   <button @click="changeView('C')">切换到C</button>
  </p>
</template>

<script>
var app = new Vue({
 el: '#app',
 data: {
  currentView: 'comA'
 },
 methods: {
  changeView: function(data){
   this.currentView = 'com'+ data　　//动态地改变currentView的值就可以动态挂载组件了。
  }
 },
 components: {
  comA: {
   template: '<p>组件A</p>'
  },
  comB: {
   template: '<p>组件B</p>'
  },
  comC: {
   template: '<p>组件C</p>'
  }
 }
});
</script>