NHibernate的，解決不了產權

Question

我有NHibenate問題。當我運行queryover時，出現錯誤「無法解析屬性：User.Name：MegaOnlineChat.Core.Entities.Message」。我做錯了什麼？

實體對象

public class EntityObject<TId> 
    { 
     public virtual Int32 Id { get; set; } 
    } 
public class User:EntityObject<Int32> 
    { 
     public virtual String Name { get; set; } 
     public virtual String Password { get; set; } 
     public virtual Boolean Admin { get; set; } 
     public virtual IList<Message> Messages { get; set; } 
    } 
public class Message:EntityObject<Int32> 
    { 
     public virtual String Text { get; set; } 
     public virtual User User { get; set; } 
     public virtual DateTime Date{ get; set; } 
    } 

映射

public class UserMapping:ClassMap<User> 
{ 
    public UserMapping() 
    { 
     Table("Users"); 
     Id(m => m.Id).GeneratedBy.Native(); 
     Map(m => m.Name).Unique().Not.Nullable(); 
     Map(m => m.Admin).Not.Nullable(); 
     Map(m => m.Password).Not.Nullable(); 

     HasMany(m => m.Messages).KeyColumn("User_id"); 
    } 
} 
public class MessageMapping:ClassMap<Message> 
{ 
    public MessageMapping() 
    { 
     Table("Messages"); 

     Id(m => m.Id).GeneratedBy.Native(); 

     Map(m => m.Text).Not.Nullable(); 
     Map(m => m.Date).Not.Nullable(); 

     References(m => m.User, "User_id").Not.Nullable(); 
    } 
} 

QueryOver

NHibernateSession.QueryOver<Message>().Where(x => x.User.Name == name).List<Message>().Last(); 

Answer 1

QueryOver是不一樣的LINQ查詢提供者。這將是更容易做：

NHibernateSession.Query<Message>().Where(x => x.User.Name == name).ToList(); 

但是，如果你想使用QueryOver，你需要明確地加入你想瀏覽的關係：

NHibernateSession.QueryOver<Message>() 
    .JoinQueryOver(x => x.User) // navigate to the user on the relationship 
    .Where(u => u.Name == name) // this restriction is on the User now 
    .List(); 

你也可以做到這一點使用的別名用戶