获取选中checkbox的label和value         

 <el-checkbox-group v-model="checkedAlarmObj">
            <el-checkbox @change="changeObj" v-for="item in alarmObj" :label="item.roleName" :key="item.roleId"
                         :value="item.roleId"/>
          </el-checkbox-group>


      checkedAlarmObj: [
          {
            roleId: 1,
            roleName: '超级管理员'
          },{
            roleId: 2,
            roleName: '系统管理员'
          },
        ],
        checkedAlarmObjIdArr: [],
        alarmObj: [],




 changeObj() {
        this.checkedAlarmObjIdArr = [];
        for (let i = 0; i < this.checkedAlarmObj.length; i++) {
          for (let j = 0; j < thi