Question

我有这些课程：

public class Event
{
  [Key]
  public int ID { get; set; }

  [Required]
  public string Name { get; set; }

  [Required]
  public DateTime Begin { get; set; }

  [Required]
  public DateTime End { get; set; }

  public string Description { get; set; }

  public virtual ICollection<EventRegistration> Registrations { get; set; }

  public virtual ICollection<EventComment> Comments { get; set; }
}

public class EventComment
{
    [Key]
    public int ID { get; set; }

    [Required]
    public int PersonID { get; set; }

    [Required]
    public int EventID { get; set; }

    [Required]
    public DateTime EntryDate { get; set; }

    [Required]
    public string Comment { get; set; }

    public int? ParentCommentID { get; set; }

    public virtual Event CommentEvent { get; set; }

    public virtual Person CommentPerson { get; set; }

    public virtual EventComment ParentComment { get; set; }

    public virtual ICollection<EventComment> ChildComments { get; set; }

}

在上下文中我有以下内容：

protected override void OnModelCreating(DbModelBuilder modelBuilder) 
 { 
     modelBuilder.Conventions.Remove<PluralizingTableNameConvention>(); 
     modelBuilder.Entity<EventComment>()
                 .HasMany(s => s.ChildComments)
                 .WithOptional()
                 .HasForeignKey(s => s.ParentCommentID);
 }

EventComments和子项正确加载。但是每个事件都会使用该EventID加载所有EventComments。 Event类只应加载没有ParentID的EventComments。我怎么能这样做？

Answer 1

如果我理解正确，你会做类似

的事情

var event = (from e in ctx.Event.Include(p=>p.EventComment) select e);

并且您不希望所有加载的EventComments，只是特定的

。

不幸的是，EF没有提供过滤.Include的机制。

然而，您可以使用此处概述的预测：

https://stackoverflow.com/a/5666403/141172

ASP.Net MVC3 EF 4.1模型代码第一个父ID构造

1 个答案: