如何使 ObjectResult 可过滤
看起来应该很简单，但我显然太笨了，无法弄清楚。我使用简单的 ObjectQuery 获取 ObjectResult；这只是数据表中的几条记录。我将其分配给 CollectionViewSource Source 属性。然后，我查看 CollectionView 的 View 属性，发现 CanFilter 和 CanSort 均为 false。当我将 DefaultView 作为 BindingListCollectionView 获取时，它显示 CanCustomFilter 为 false。由于这些是只读的，我无法更改这些值。现在，我想对检索到的数据设置过滤器（或排序），而无需返回 SQL Server，但我一生都找不到一种方法来获取这些属性设置为 true 的数据。
我尝试使用 ObjectResult.AsQueryable ，结果确实有 CanFilter 和 CanSort true，但这将视图类型从 < code>System.Windows.Data.BindingListCollectionView 到 MS.Internal.Data.EnumerableCollectionView 中，我找不到一种方法来转换它EnumerableCollectionView 返回到 BindingListCollectionView。
任何指示将不胜感激。
It seems like it should be simple, but I'm apparently too dense to figure it out. I'm getting an ObjectResult using a simple ObjectQuery; it's just a few records in the data table. I assign it to a CollectionViewSource Source property. I then look at the View property of the CollectionView and see that CanFilter and CanSort are both false. When I get the DefaultView as a BindingListCollectionView, it shows that the CanCustomFilter is false. Since these are read-only, I cannot change the value(s). Now I'd like to set a filter (or sort) on the retrieved data without making a trip back to SQL Server, but for the life of me I cannot find a way to get the data with these properties set true.
I tried using ObjectResult.AsQueryable<T>() and the result DOES have CanFilter and CanSort true, but that changes the View type from System.Windows.Data.BindingListCollectionView into MS.Internal.Data.EnumerableCollectionView and I cannot find a way to cast that EnumerableCollectionView back into a BindingListCollectionView.
Any pointers would be greatly appreciated.
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我认为这种偏差的主要原因是
BindingListCollectionView无法过滤或排序任何IQueryable对象（不知道为什么），尽管在设置上执行查询源属性。最简单的方法是使用ToList() 方法，该方法执行查询，但是形成的List可以通过BindingListCollectionView进行排序和过滤代码>I think the main reason of such deviation is that
BindingListCollectionViewcan't filter or sort anyIQueryableobjects (don't know why), in spite of execution of query on settingSource property. The simpliest way is to useToList<T>()method, which executes query, but formedList<T>can be sorted and filtered byBindingListCollectionView