elementUI实现表格上移下移效果

<el-table-column
    label="操作"
    align="center"
    width="200"
    class-name="small-padding fixed-width"
>
     <template slot-scope="scope">
         <el-button
              size="mini"
              type="text"
              icon="el-icon-edit"
              @click="handleUp(scope.$index, scope.row)"
         >向上
         </el-button>
         <el-button
              size="mini"
              type="text"
              icon="el-icon-key"
              @click="handleDown(scope.$index, scope.row)"
          >向下
      </el-button>
    </template>
</el-table-column>

handleUp(index, row) {
  if (index <= 0) {
     console.log('已经是第一条了')
   } else 
      const upData = this.userList[index - 1]
      this.userList.splice(index - 1, 1)
      this.userList.splice(index, 0, upData)
   }
},
handleDown(index, row) {
  if (index == (this.userList.length - 1)) {
     console.log('已经是最后一条了')
   } else {
      const downData = this.userList[index + 1]
      this.userList.splice(index + 1, 1)
      this.userList.splice(index, 0, downData)
   }
}