Edit in JSFiddle

Vue.component('component-plus', {
	template: '#componentCount',
  props: ['compoCount'],
  methods: {
  	plus: function() {
    	this.compoCount +=1
    }
  }
})

/* Vue.component('component-plus', {
  template: `
    <button @click="plus">
      我被按了 {{ compoCount }} 下
    </button>
  `,
  props: {
    compoCount: String
  },
  methods: {
    plus: function() {
      this.compoCount +=1
    }
  }
}) */

let vm = new Vue({
	el: '#app',
 	data: {
    count: 0
  },
})

<div id="app">
  <div 
    is="component-plus"
    :compo-count='count'
  >  
  </div>
  <component-plus 
    :compo-count='count'
  >  
  </component-plus>
</div>

<script type="text/x-template" id="componentCount">
	<button @click="plus">
  	我被按了 {{ compoCount }} 下
  </button>
</script>