element-UI dropdown 传多个参数

<el-dropdown class="dropdown_btn" @command="handleCommand">
   <span class="el-dropdown-link">更多</span>
   <el-dropdown-menu slot="dropdown">
      <el-dropdown-item :command="beforeHandleCommand('a',scope.row)">设备订单</el-dropdown-item>
      <el-dropdown-item :command="beforeHandleCommand('b',scope.row)">设备位置</el-dropdown-item>
      <el-dropdown-item :command="beforeHandleCommand('c',scope.row)">设备转移</el-dropdown-item>
   </el-dropdown-menu>
</el-dropdown>

handleCommand(command){
   switch (command.command) {
      case "a":
      　　// 设备订单
      　　this.toOrder(command.row.deviceId)
       　　break;
       case "b":
       　　// 设备位置
       　　// this.deleteUser(command.index,command.row);
       　　break;
       case "c":
       　　// 设备转移
       　　// this.assignRole(command.index,command.row);
        　　break;
     }
},
beforeHandleCommand(item,row){
  return {
     'command': item,
     'row': row
  }
}