1. 案例代码

<el-row v-for="(item,index) in formData.acTypeCrews":key="index"class="acTypeCrew-row"><el-col :span="24"><el-checkbox v-model="item.checkbox"@change="(query) => changeSelected(query, index)">{{item.acTypeCrew}}</el-checkbox></el-col>
</el-row>

2. 核心代码公式：
   事件名称: @change
   默认参数: (query)
   绑定事件: => changeSelected
   默认参数+ 新参数: (query, index)

@change="(query) => changeSelected(query, index)"

// 改变选中状态
changeSelected (val, index) {// 第几行被勾选或取消勾选console.log('val', val, index)
},