<script src="https://unpkg.com/vue/dist/vue.js"></script>
<div id="example-2">
  <simple-counter></simple-counter>
  <simple-counter></simple-counter>
  <simple-counter></simple-counter>
</div>
<script>
var xx=Vue.extend({
    template: '<h1>{{message}}</h1>',
    data:function(){
        return {
            message:'good'
        }
    }
});
Vue.component('simple-counter',xx)
var vm = new Vue({
    el:"#example-2"
}
)
</script>

输出

image.png

参考

vue.extend, vue.component 区别 - 夜聆风的回答 - SegmentFault