利用组件父子传值做的购物车

html代码：

     <div class="container">
         <tab></tab>
     </div>

js 代码：

    <script src="vue.js"></script>
    <script>
        Vue.component('tab',{
            template:`
               <table class="table table-bordered text-center">
                  <thead>
                    <tr>
                        <th class="text-center">编号</th>
                        <th class="text-center">名称</th>
                        <th class="text-center">单价</th>
                        <th class="text-center">数量</th>
                        <th class="text-center">总价</th>
                    </tr>
                </thead>
               <chld v-bind:frulit='arr'></chld>
            </table>
        `,
         data:function(){
            return{
                arr:[
                {name:"香蕉",danjia:"8",num:"2",price:"16"},
                {name:"苹果",danjia:"5",num:"3",price:"15"},
                {name:"鸭梨",danjia:"3",num:"1",price:"3"}
            ] 
           }
        }   
    })
    
    Vue.component('chld',{
        props:['frulit'],
        template:`
             <tbody>
                    <tr v-for="(v,ind) in frulit">
                        <td>{{ind+1}}</td>
                        <td>{{v.name}}</td>
                        <td>{{v.danjia}}</td>
                        <td>
                        <button @click="jia(ind)">+</button>
                        <span>{{v.num}}</span>
                        <button @click="jian(ind)">-</button></td>
                        <td>{{v.price}}</td>
                    </tr>
                    <tr>
                        <td colspan="5">总计：{{arrs}}元</td>
                    </tr>
                </tbody>

        `,
        data:function(){
            return{
                arrs:34.00
            }
        },
        methods:{
            jia:function(ind){
                // 数量
                this.frulit[ind].num++;
                //  小计
                this.frulit[ind].price=this.frulit[ind].num*this.frulit[ind].danjia;
                this.tal();
            },
            jian:function(ind){
                // 数量
                if(this.frulit[ind].num>1){
                    this.frulit[ind].num--;
                            //  小计
                    this.frulit[ind].price=this.frulit[ind].num*this.frulit[ind].danjia;
                    this.tal();
                }
            },
            //  总价
             tal:function(){
            for(var i=0,j=0;i<this.frulit.length;i++){
                j+=Number(this.frulit[i].price)
            }
            this.arrs=j
          }
        }  
    })
    new Vue({
        el:".container"
    })
</script>