Telerik Kendo UI MVC Grid 数据源结果到对象列表答案

【问题标题】：Telerik Kendo UI MVC Grid datasourceresult to list of objectsTelerik Kendo UI MVC Grid 数据源结果到对象列表
【发布时间】：2016-05-31 12:47:07
【问题描述】：

Telerik Kendo UI MVC Grid 填充了来自 T1ViewModel 的数据（从 DB1 中的 T1 和 DB2 中的 T2 连接，其中 T1 和 T2 是表，DB1 和 DB2 是数据库）。

T1 有一个 ShopID 列，并且 ShopName 列存在于 DB2 的 T2 中。我在两个上下文中使用 EntityFramwork。

将 T1 数据加载到内存中，然后与 T2 连接。由于我每页只显示 10 条记录，因此 T1 和 T2 有数百万条记录，并且这种连接发生在影响性能的每个页面更改上。

然后我使用 DataSoureceRequest 过滤 T1 记录。

public ActionResult T1_Read([DataSourceRequest] DataSourceRequest request)
{
using(var context = new DB1Context())
{//Get requested records from T1 into T1ViewModel which has shop name property
DataSourceResult result = context.T1.select(r => new T1ViewModel{ShopId = r.ShopID.....}).ToDataSourceResult(request)
}
IEnumerable<T1ViewModel> T1RecordsFiltered = result.data;
var ShopIds = T1RecordsFiltered.Select(T => T.ShopID);

using(var context = new DB2Context())
{//Get the T2 records that has matching ShopId in the list(ShopIds)
var T2RecordsFiltered = context.T2.Where(T => ShopIds.Contains(T.ShopID)).ToList();
}
var t1ViewModel = from t1rf in T1RecordsFiltered
              join t2rf in T2RecordsFiltered on t1rf.ShopID equals t2rf.ShopID into t2rfGroup
              from t2rfg in t2rfGroup.DefaultIfEmpty()
              select new { t1rf, t2rfg };

var t1ViewModelDetails = t1ViewModel.Select(t =>
            {
                t.t1rf.ShopName = t.t2rfg.ShopName;
                return t.t1rf;
            });           
result.data = t1ViewModelDetails;

return Json(result, JsonRequestBehavior.AllowGet);  
}

现在的问题是我的网格也是可分组的。但是当我使用该功能时，result.data 具有 AggregateFunctionsGroup 列表。所以我无法将 result.data 转换为 T1ViewModel 列表。这是正确的做法吗？有更好的方法吗？

【问题讨论】：

标签： asp.net-mvc entity-framework kendo-ui telerik kendo-asp.net-mvc

【解决方案1】：

找到了解决办法。我没有依赖 dataSourceResult 的数据，而是使用 ToDataSourceResult 重载方法来创建 t1ViewModels 列表并修改 tViewModels 以更新 shopName，如下所示。

public ActionResult T1_Read([DataSourceRequest] DataSourceRequest request)
    {
        List<T1ViewModel> t1ViewModels = new List<T1ViewModel>();
        DataSourceResult result;
        using (var context = new DB1Context())
        {//Get requested records from T1 into T1ViewModel which has shop name property
            result = context.T1.ToDataSourceResult(request, t =>
            {
                T1ViewModel tvm = T1ViewModel.FromModel(t);
                t1ViewModels.Add(tvm);
                return tvm;
            });
        }
        var ShopIds = t1ViewModels.Select(T => T.ShopID);

        using (var context = new DB2Context())
        {//Get the T2 records that has matching ShopId in the list(ShopIds)
            var T2RecordsFiltered = context.T2.Where(T => ShopIds.Contains(T.ShopID)).ToList();
        }
        var t1ViewModelDetails = from t1vm in t1ViewModels
                                 join t2rf in T2RecordsFiltered on t1vm.ShopID equals t2rf.ShopID into t2rfGroup
                                 from t2rfg in t2rfGroup.DefaultIfEmpty()
                                 select new { t1vm, t2rfg };

        t1ViewModelDetails.Select(t =>
        {
            t.t1vm.ShopName = t.t2rfg.ShopName;
            return t.t1vm;
        });

        return Json(result, JsonRequestBehavior.AllowGet);
    }

【讨论】：