SOURCE

new Vue({
  el: '#app',
  data: {
    datalist: [
      {'id': 1, 'name': 'iphone X', 'price': 5000, 'number': 1},
      {'id': 2, 'name': '小米8', 'price': 2200, 'number': 2},
      {'id': 3, 'name': '华为Meta30 Pro', 'price': 5600, 'number': 1}
    ],
    datagroup: []
  },
  methods: {
		getSum(){
      var sum = 0;
      for(i in datagroup){
        sum += this.datagroup[i].price * this.datagroup[i].number;
      }
      return sum;
    }
	}
})

<div id="app">
  <div>
    <p v-for="data in datalist"><input type="checkbox" v-model="datagroup" :value="data"/> {{ data }}</p>
  </div>
  总计: {{ getSum() }}
  <p>{{ datagroup }}</p>
</div>

<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>

body{
  background-color: #5a5;
}