NHibernate的/ LINQ的：NHibernate.QueryException：无法解析属性：MyNamespace.MyObject：中Profile.class [英] Nhibernate/Linq: NHibernate.QueryException : could not resolve property: Profile.class of: MyNamespace.MyObject

问题描述

我有我的LINQ查询的问题。我试图筛选基于选择的值对象。我们使用它返回一个System.Linq.Expressions.Expression并使用它来创建NHibernate的查询的查询模式。这是我的LINQ表达式

I'm having an issue with my linq query. I am trying to filter objects based on selected values. We use a query model which returns a System.Linq.Expressions.Expression and uses it to create an nhibernate query. Here is my linq expression.

x =>(request.InitialLoad
     || (!request.InitialLoad
         && (Enum.GetValues(typeof(MyType)).Length == request.MyTypes.Length
             ||
             (Enum.GetValues(typeof(MyType)).Length != request.MyTypes.Length
              &&
              ((request.MyTypes.Contains((int)MyType.Referrals)
                && x.Post.PostType == StatusPostType.Referral)
               ||
               (request.MyTypes.Contains((int)MyType.Businesses)
                && x.Post.Profile is BusinessProfile)
               ||
               (request.MyTypes.Contains((int)MyType.Members) 
                && x.Post.Profile is UserProfile)
              )
             )
            )
        )
    )
    && x.Profile.Equals(request.Profile);

的映射（我们使用流利）是这样的：

The mappings (we are using fluent) Look like this:

为MyObject（邮政属性）：

MyObject (Post property):

References(x => x.Post, "PostId");

MyObject.Post（配置文件属性）：

MyObject.Post (Profile property):

References(x => x.Profile, "ProfileId");

在更改 x.Post.Profile是SOMETYPE 到 x.Post.Profile.GetType（）== typeof运算（SOMETYPE），它抛出一个不同的错误，这是

When I change x.Post.Profile is SomeType to x.Post.Profile.GetType() == typeof(SomeType) it throws a different error, which is

System.ArgumentOutOfRangeException：
指数超出范围。必须是
非负并小于
中的集合的大小。参数名称索引：

System.ArgumentOutOfRangeException : Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

当我拿出了类型比较布尔表达式，只有在介绍人表达离开的时候，它工作正常进行过滤仅上一个选项。

When I take out the type comparison boolean expressions and only leave in the Referrals expression, it works fine for filtering only on that one option.

的属性不以任何方式被模型修改。他们是用默认的get / set虚拟属性。

The properties are not modified in any way by the model. They are virtual properties with the default get/set.

任何想法？

推荐答案

我敢肯定NHibernate.Linq不直接支持类类型过滤。如果你需要的类型来区分，我会在被设置为在子类中适当的值的基类（可能是一个枚举），使用属性值。然后，您可以执行这样的比较：

I'm pretty sure NHibernate.Linq does not support filtering on class type directly. If you need to distinguish between the types, I would use a property value on the base class (probably an enum) that is set to the proper value in the child classes. You can then perform your comparison like this:

x.Post.Profile.Type = ProfileTypes.BusinessProfile

在构造函数中的子类只需设置该属性静态的，与NHibernate映射它，并设置更新= FALSE 的属性映射。虽然有点不雅，这应该给你你要寻找的结果。

Just set this property statically in the constructor for the child classes, map it with NHibernate, and set update=false for the property mapping. Although somewhat inelegant, this should give you the results you're looking for.

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