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| <template>
| <div>
| {{ a }}
| <br><br>
| {{ result }}
| <br><br>
| {{ b }}
| <br><br>
| <el-button @click="b++">123123</el-button>
|
| <br><br>
| {{ '父组件传值给子组件：'+car }}
|
| <br><br>
| <el-button @click="gaveParent">子组件传递数据给父组件</el-button>
| </div>
| </template>
| <script setup>
| import {ref,computed,watch,defineProps,defineEmits} from 'vue'
| let a = $ref([1,2,3,4,5,6])
| let b =ref(0)
|
| let props = defineProps({
| car:{
| String,
| default:0
| }
| })
|
| const emit = defineEmits(['changeNum'])
| const gaveParent = () => {
| emit('changeNum','子组件给父组件传值了')
| }
|
| //使用计算属性过滤出数组中小于2的
| const result=computed( () => {
| return a.filter(item => item>2)
| })
|
| watch(b,(newValue,oldValue) => {
| console.log("改变了当前值："+newValue+" "+oldValue)
| })
|
| </script>
| <style scoped>
|
| </style>
|
|
