Entity framework 实体框架4.1列名称无效

我有两个表格新闻和新闻评论。我遵守命名规则

结构新闻评论

public class NewsComment : BaseComment
{
    public int NewsId { get; set; }

    public virtual News News { get; set; }      
}

但查询返回异常无效的列名“News\u Id”。我知道这个异常在“表不相关”列中创建了什么

CREATE TABLE [dbo].[NewsComments](
[Id] [int] IDENTITY(1,1) NOT NULL,
[NewsId] [int] NOT NULL,
[Text] [varchar](max) NOT NULL,
[UserId] [int] NOT NULL,
[CommentDate] [datetime] NOT NULL,
[Ip] [varchar](40) NOT NULL, CONSTRAINT [PK_NewsComments] PRIMARY KEY CLUSTERED([Id] ASC )WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]) ON [PRIMARY]

BaseComment

public abstract class BaseComment : BasePersistentEntity, IComment
{

    public int UserId { get; set; }

    public virtual BaseUser User { get; set; }

    [Display(ResourceType = typeof(FrameworkResurce), Name = "CommentText")]
    public string Text { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "CommentDate")]
    public DateTime CommentDate { get; set; }


    public string Ip { get; set; }
}

public abstract class BaseContent : BasePersistentEntity
{
    [Display(ResourceType = typeof(FrameworkResurce), Name = "Keywords")]
    public string Keywords { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "TitleTranslit")]
    public string TitleTranslit { get; set; }

    [Required(ErrorMessageResourceType = typeof(FrameworkResurce), ErrorMessageResourceName = "IsTextEmpty")]
    [Display(ResourceType = typeof(FrameworkResurce), Name = "Title")]
    public string Title { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "Description")]
    public string Description { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "Contents")]
    public string Contents { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "DatePublish")]
    public DateTime DatePublish { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "AuthorPublish")]
    public string AuthorPublish { get; set; }

    [Display(ResourceType = typeof(FrameworkResurce), Name = "Author")]
    public string Author { get; set; }

    [Display(ResourceType = typeof(FrameworkResurce), Name = "AuthorUrl")]
    public string AuthorUrl { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "Views")]      
    public int Views { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "Comments")]
    public int Comments { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "IsComment")]
    public bool IsComment { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "SumVote")]
    public int SumVote { get; set; }


    [Display(ResourceType = typeof(FrameworkResurce), Name = "VoteCount")]
    public int VoteCount { get; set; }

    [NotMapped]
    [Display(ResourceType = typeof(FrameworkResurce), Name = "Rating")]
    public double Rating
    {
        get
        {
            if (VoteCount > 0)
            {
                return Math.Round((float)SumVote/VoteCount, 2);
            }

            return 0;
        }
    }
}

新闻

public class News : BaseContent
{
    [Display(ResourceType = typeof(NewsResurce), Name = "NewsImage")]
    public string NewsImage { get; set; }

    public virtual ICollection<NewsCommentView> CommentViews { get; set; }
}

    [GridAction]
    public ActionResult AjaxCommentsBinding()
    {
        return View(new GridModel<NewsComment>
        {
            Data = GetComments()
        });
    }

CREATE VIEW [dbo].[NewsCommentViews]
AS
SELECT     dbo.NewsComments.NewsId, dbo.NewsComments.Text, dbo.NewsComments.UserId, dbo.NewsComments.CommentDate, dbo.NewsComments.Ip, 
                      dbo.Roles.RoleName, dbo.Users.UserName, dbo.Users.DateRegistered, dbo.NewsComments.Id, dbo.Users.Avatar
FROM         dbo.NewsComments INNER JOIN
                      dbo.Users ON dbo.NewsComments.UserId = dbo.Users.Id INNER JOIN
                      dbo.Roles ON dbo.Users.RoleId = dbo.Roles.Id

[Table("NewsCommentViews")]
    public class NewsCommentView : NewsComment
    {
        public string RoleName { get; set; }

        public string UserName { get; set; }

        public DateTime DateRegistered { get; set; }

        public string Avatar { get; set; }
    }

查询

private IEnumerable<NewsComment> GetComments()
    {
        var news = NewsCommentRepository.AllIncluding(c=>c.User,c=>c.News);
        return news;
    }

private DataRepository<NewsComment> NewsCommentRepository
        {
            get { return DataRepository<NewsComment>.Repository; }
        }

public class DataRepository<T> where T : BasePersistentEntity
{
    public static DataRepository<T>  Repository
    {
        get
        {
            return new DataRepository<T>();
        }
    }

    private readonly SGNContext<T> context = new SGNContext<T>();

    public IQueryable<T> All
    {
        get { return this.context.Table; }
    }

    public IQueryable<T> AllIncluding(params Expression<Func<T, object>>[] includeProperties)
    {
        IQueryable<T> query = this.context.Table;
        return includeProperties.Aggregate(query, (current, includeProperty) => current.Include(includeProperty));
    }

    public T Find(int id)
    {
        return this.context.Table.Find(id);
    }

    public void InsertOrUpdate(T country)
    {
        if (country.Id == default(int))
        {
            // New entity
            this.context.Table.Add(country);
            Save();
        }
        else
        {
            // Existing entity
            this.context.Entry(country).State = EntityState.Modified;
            Save();
        }
    }

    public void Delete(int id)
    {
        var country = this.context.Table.Find(id);
        this.context.Table.Remove(country);
        this.Save();
    }

    private void Save()
    {
        this.context.SaveChanges();
    }
}

新闻评论视图

public class News : BaseContent
{
    [Display(ResourceType = typeof(NewsResurce), Name = "NewsImage")]
    public string NewsImage { get; set; }

    public virtual ICollection<NewsCommentView> CommentViews { get; set; }
}

    [GridAction]
    public ActionResult AjaxCommentsBinding()
    {
        return View(new GridModel<NewsComment>
        {
            Data = GetComments()
        });
    }

CREATE VIEW [dbo].[NewsCommentViews]
AS
SELECT     dbo.NewsComments.NewsId, dbo.NewsComments.Text, dbo.NewsComments.UserId, dbo.NewsComments.CommentDate, dbo.NewsComments.Ip, 
                      dbo.Roles.RoleName, dbo.Users.UserName, dbo.Users.DateRegistered, dbo.NewsComments.Id, dbo.Users.Avatar
FROM         dbo.NewsComments INNER JOIN
                      dbo.Users ON dbo.NewsComments.UserId = dbo.Users.Id INNER JOIN
                      dbo.Roles ON dbo.Users.RoleId = dbo.Roles.Id

[Table("NewsCommentViews")]
    public class NewsCommentView : NewsComment
    {
        public string RoleName { get; set; }

        public string UserName { get; set; }

        public DateTime DateRegistered { get; set; }

        public string Avatar { get; set; }
    }

---

您的SQL在用户和id之间没有下划线

---

从数据库更新EDMX（通过右键单击菜单）并检查映射。

问题在于

新闻

和

新闻评论视图

之间的关系：关系的一端是

新闻。评论视图

集合。但另一端是而不是您可能期望的

新闻评论视图.News

。为什么？因为属性

News

不是在

newcommentview

类上声明的，而是在基类上声明的。现在EF不允许实体参与与导航属性的关系，该属性未在该实体类本身上声明，但仅在基类中声明

因此，因为您没有流畅的映射，EF仅通过约定定义所有关系。会发生什么

• News

  声明了一个导航属性

  CommentViews

  ，并指向

  newcommentview

  类
• EF找不到类型为

  News

  的反向属性，该属性在

  NewsCommentView

  类中声明为。（有一个，但它在基类中，不算在内。）
• 因此，EF假设关系的另一端在

  NewsCommentView

  类中是未公开的
• 未公开意味着：EF既没有导航属性也没有外键属性，并且将假定数据库表/view

  NewsCommentViews

  中必要的外键列将具有标准的常规名称
• 此常规名称是

  NameOfEntityClass\u PKPropertyName

  ->

  News\u Id

您在视图中的真实姓名是

NewsId

。因此，EF查询不存在的列

News\u Id

，因此出现异常

当MVC视图访问

NewsComment.News.CommentViews

时，可能会由于延迟加载而触发此异常

您可以通过在Fluent API中明确指定FK列名来解决此问题（据我所知，没有Fluent映射没有其他方法）：

公共类MyContext:DbContext
{
// ...
模型创建时受保护的覆盖无效（DbModelBuilder modelBuilder）
{
modelBuilder.Entity（）
.HasMany（n=>n.CommentViews）
.WithRequired（）//nc.News将引发异常
//因为nc.News在基类中
.Map（a=>a.MapKey（“NewsId”）；
}
}

---

但是注意：请注意

新闻评论视图.News

不是属于

新闻.commentview

的关系的另一端。这意味着，如果在

News.CommentViews

集合中有

newscordview

，则

newscordview.News

不会指向该

News

对象。另一端不可见且未在模型中暴露。上面的映射只修复了FK列名问题，但不会更改约定将创建的关系（除了可能将关系更改为“必需”而不是“可选”）。

能否显示导致异常的查询？也许还有

News

和

BaseComment

类。在Fluent API中是否有映射代码？能否显示引发异常的查询？接下来的两个问题：1）NewsCommentView的外观如何？2） 您能否准确显示使用查询的代码

GetComments（）

？它只是一个

IQueryable/IEnumerable

，因此查询不会在

GetComments

中执行，而是在其他地方执行。请准确地指出引发异常的那一行。模型中的

NewsCommentView

类是如何定义的？现在我看到您编辑了问题。您在哪里将属性NewsId映射到（不存在）列News\u Id搜索你的代码。如果已经在代码中更正了输出文件，请尝试删除该文件。