MVC Contrib 网格在 .OrderBy() 上失败并出现 NHibernate 异常

Question

我一直在关注 this 使用 MVC contrib 创建网格的不错的演练。

然而，我的版本使用的是 NHibernate，而不是 linq 到实体。

代码在排序之前运行良好。

    public ActionResult Index(string clientName, int? countryId, GridSortOptions gridSortOptions, int? page)
    {
        var clientList = from c in this.ClientRepository.Query
                         select new ListedClientViewModel(c);

        //Set default sort column
        if (string.IsNullOrWhiteSpace(gridSortOptions.Column))
            gridSortOptions.Column = "ClientName";

        // Filter on clientName
        if (!string.IsNullOrWhiteSpace(clientName))
            clientList = clientList.Where(c => c.ClientName.StartsWith(clientName));

        // Filter on country
        if (countryId.HasValue)
            clientList = clientList.Where(c => c.CountryId == countryId);

        // Order and page the clients
        var clientPageList = clientList
            //Sorting causes error.
            //.OrderBy(gridSortOptions.Column, gridSortOptions.Direction)
            .AsPagination(page ?? 1, 10);

        var clientListContainer = new ClientListContainerViewModel
        {
            ClientPageList = clientPageList,
            GridSortOptions = gridSortOptions
        };

        return View(clientListContainer);
    }

如果我取消注释 .OrderBy(gridSortOptions.Column, gridSortOptions.Direction) 行，它将在使用 System.NotSupportedException {"NewExpression"} 到达视图时失败

有什么办法可以解决这个问题吗？

非常感谢，Kohan。

Answer 1

解决了...只需在应用过滤和排序之后再转换视图模型。

  var clientList = this.ClientRepository.Query;

  ...
  ...

  // Order and page the clients
  var clientPageList = clientList
       //Sorting no longer causes error.
       .OrderBy(gridSortOptions.Column, gridSortOptions.Direction)
       .Select(c => new ListedClientViewModel(c))
       .AsPagination(page ?? 1, 10);