出现“无法将 PersistentGenericSet 转换为 ISet”错误

我收到此错误：

无法转换类型的对象 'NHibernate.Collection.Generic.PersistentGenericSet1[IocWinFormTestEntities.People]' to type 'System.Collections.Generic.ISet1[IocWinFormTestEntities.People]'。

实体：

public class Event 
{
    public Event()
    {
        this.People = new HashSet<People>();
    }
    public virtual Guid Id { get; private set; }

    public virtual ISet<People> People { get; set; }
}

地图覆盖类：

public class EventMapOverride : IAutoMappingOverride<Event>
{
    public void Override(AutoMapping<Event> mapping)
    {
        mapping.HasMany(c => c.People)
            .AsSet()
            .Cascade.AllDeleteOrphan();
    }
}

从流畅的自动映射器生成 hbm：

<set cascade="all-delete-orphan" name="People">
    <key>
        <column name="Event_id" />
    </key>
    <one-to-many class="IocWinFormTestEntities.People, IocWinFormTestEntities, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
</set>

怎么了？

你的问题是你正在使用ISet http://msdn.microsoft.com/en-us/library/dd412081.aspx in System.Collections.Generic名称空间，但 nHibernate 期望 ISet 是Iesi.Collections.Generic.ISet<>。因此，将您的属性定义更改为

public virtual Iesi.Collections.Generic.ISet<People> People { get; set; }

如果你想使用.net 4ISet<>界面，通过这个article http://nhibernate.info/blog/2011/03/15/using-lt-set-gt-in-mappings-without-iesi-collections-net-4.html