1.component.vue

<template>
  <div id="app">
    <component :is="key"></component>
  </div>
</template>
 <script>
var componentA = {
  template: `<div style="color:red">我是A组件</div>`
};

var componentB = {
  template: `<div style="color:blank">我是B组件</div>`
};

var componentC = {
  template: `<div style="color:pink">我是C组件</div>`
};
export default {
  name: "component",
  data() {
    return {
      key: "comC"
    };
  },
  methods: {
  },
  components: {
    comA: componentA,
    comB: componentB,
    comC: componentC
  }
};

</script>