Question

我已经尝试过像这样在领域集合中过滤IQueryable <>：

public class Configuration
{
    public bool IsFilter { get; set; }

    public IQueryable<Model> ApplyFilter(IQueryable<Model> collection)
    {
        var filterCollection = collection;

        filterMessages = filterMessages.Where(IsFilter || !IsFilter && w.IsFilter);

        return filterCollection;
    }
}

当我使用ApplyFilter时，我会得到NotSupportedException

我认为这是因为Configuration的对象已经被处置和收集了。

如何使用类似的过滤器？

Answer 1

如果您只是想通过包含的bool属性过滤Realm模型，则可以使用Linq Where（{Where(model => model.IsFilter == IsFilter)）

示例：

public class Configuration
{
    public bool IsFilter { get; set; }

    public IQueryable<ItemModel> ApplyFilter(IQueryable<ItemModel> realmQuery)
    {
        return realmQuery.Where(model => model.IsFilter == IsFilter);
    }
}

示例用法：

// Assuming you have an `Configuration` instance already created:
configuration.IsFilter = true;
realmList.ItemsSource = configuration.ApplyFilter(realmList.ItemsSource as IQueryable<ItemModel>);

Answer 2

请注意，当前，该属性必须位于条件的左侧。这意味着

var oldDogs = realm.All<Dog>().Where(dog => 7 < dog.Age); // INVALID query, do not copy
is illegal and would have to be changed into the equivalent

var oldDogs = realm.All<Dog>().Where(dog => dog.Age > 7); // Fixed

https://realm.io/docs/dotnet/latest/api/linqsupport.html

感谢@SushiHangover

但是我认为“领域”应该提供描述信息。

处置过滤器数据时如何在领域中使用I过滤器

2 个答案:

示例：

示例用法：