LINQ to Entities 不支持指定的类型成员“Locale_Section”。

Question

我在stackoverflow上遇到了一些与我的here类似的问题，但它们看起来并没有深入到连接表中，而且我看不到任何适用于我的代码的东西，所以我希望有人可以查看我的代码位并告诉我为什么我得到了

LINQ to Entities 不支持指定的类型成员“Locale_Section”。仅支持初始化器、实体成员和实体导航属性。

        private object SetNavItems(string Category, byte CultureID)
    {
        using (var db = new Compleate())
        {
            return (from n in db.Navigation
                    where n.Category == Category && n.Section.Locale_Section.CultureID == CultureID
                    orderby n.Position
                    select new
                    {
                        n.Section.Locale_Section.Title,
                        n.Section.LinkAddress
                    }).ToList();
        }
    }

导航.cs

    [Table("Navigation")]
public class Navigation
{
    [Key, Required, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int NavigationID { get; set; }

    [Required, MaxLength(16), Column(TypeName = "varchar")]
    public string Category { get; set; }

    [Required]
    public Int16 SectionID { get; set; }

    [ForeignKey("SectionID")]
    public virtual Section Section { get; set; }

    [Required]
    public byte Position { get; set; }
}

Ssection.cs

    [Table("Section")]
public class Section
{
    [Key, Required, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public Int16 SectionID { get; set; }

    public Int64 LogoFileID { get; set; }

    [ForeignKey("LogoFileID")]
    public virtual File File { get; set; }

    [Required, MaxLength(15), Column(TypeName = "varchar")]
    public string RouteName { get; set; }

    [Required, MaxLength(15), Column(TypeName = "varchar")]
    public string Type { get; set; }

    [NotMapped]
    public string LinkAddress
    {
        get
        {
            return Type + "/" + RouteName;
        }
    }

    [NotMapped]
    public virtual Locale_Section Locale_Section { get; set; }
}

Locale_Section.cs

    [Table("Locale_Section")]
public class Locale_Section
{
    [Key, Required, Column(Order = 0)]
    public Int16 SectionID { get; set; }

    [ForeignKey("SectionID")]
    public virtual Section Section { get; set; }

    [Key, Required, Column(Order = 1)]
    public byte CultureID { get; set; }

    [ForeignKey("CultureID")]
    public virtual Culture Culture { get; set; }

    [Required, MaxLength(250)]
    public string Title { get; set; }

    public string Synopsis { get; set; }
}

Answer 1

您已将Section 实体中的Section_Locale 属性标记为NotMapped。这意味着该属性对于您的映射是未知的，并且无法在 Linq-to-Entities 查询中转换为 SQL。如果不映射它或将所有 Navigation 实例加载到您的应用程序，您就不能使用该属性，例如首先调用 ToList 或 AsEnumerable（这很可能是非常糟糕的解决方案）。