首先看官方文档的示例:
需要注意的是:
1、default-active的值是字符串,那么index绑定的值也要是字符串,且数字对应。不能default-avtive绑定的是1,而menu-item的index绑定的是45
2、default-active的值是当前选中menu-item项的index
所以el-menu-item的index项一定要和default-active对应起来。
javascript
<el-menu
:default-active="activeIndex"
class="el-menu-demo"
mode="horizontal"
@select="handleSelect"
>
<el-menu-item index="1">Processing Center</el-menu-item>
<el-sub-menu index="2">
<template #title>Workspace</template>
<el-menu-item index="2-1">item one</el-menu-item>
<el-menu-item index="2-2">item two</el-menu-item>
<el-menu-item index="2-3">item three</el-menu-item>
<el-sub-menu index="2-4">
<template #title>item four</template>
<el-menu-item index="2-4-1">item one</el-menu-item>
<el-menu-item index="2-4-2">item two</el-menu-item>
<el-menu-item index="2-4-3">item three</el-menu-item>
</el-sub-menu>
</el-sub-menu>
<el-menu-item index="3" disabled>Info</el-menu-item>
<el-menu-item index="4">Orders</el-menu-item>
</el-menu>
<script lang="ts" setup>
import { ref } from 'vue'
const activeIndex = ref('1')
const handleTest = (key,keyPath) => {
console.log('打印输出menuSelect事件的参数---',activeIndex.value,key,keyPath)
}
</script>
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再次点击其他项
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为了避免页面刷新时menu组件的选中样式消失,所以在每次点击的时候我们要将default-active重新赋值。这样:default-active绑定的就是动态的了。
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