vue select 组件父子通信的问题，如下图和代码

Question

问题 select默认没有报错，一选择就报错了，值都能取到 代码 父组件 <template> <div> <comSelect :cityActived="cityActived" @childToFather="fatherFn($event)"></comSelect> {{cityActived}} </div> </template> <script> import comSelect from '@/components/comSelect' export default { components:{ comSelect }, data(){ return{ cityActived:1 } }, methods:{ fatherFn(msg){ this.cityActived = msg } } } </script> 子组件 <template> <div> <select v-model="cityActived" @change="childFn()"> <option v-for="item in city" :key="item.id" :value="item.id">{{item.name}}</option> </select> </div> </template> <script> export default { props:['cityActived'], data(){ return{ city:[ {id:1,name:"北京"}, {id:2,name:"上海"}, {id:3,name:"广州"}, {id:4,name:"深圳"}, ] } }, methods:{ childFn(){ this.$emit('childToFather',this.cityActived) } } } </script>