.NET MVC循环引用问题，实体

问题描述：

我知道其他人张贴了关于这一点，但我无法找到这似乎符合我的问题是什么的答案。虽然我是超级新的.NET所以我可能只是不明白的东西。

I know others have posted about this, but I can't find an answer that seems to match what my question is. Although I am super new to .net so I may just not understand something.

我的网站有一个项目对象，这是由一个特定的用户所拥有。该项目有另一种模式用于额外的信息，其他用户可以添加。

My site has a project object, which is owned by a particular user. The project has another model for extra info that other users can add.

我的模型是这样的：

项目

在项目业主FK
其他的东西

信息

项目FK
在信息所有者FK
其他的东西

不过，我得到错误的引用关系将导致这是不允许的周期性引用。

But I am getting error The referential relationship will result in a cyclical reference that is not allowed.

我认为这是冷门，我有一个FK这两个项目和信息的用户。但用户是不同的，所以我不能干掉一个。有没有办法告诉它？

I think it is upset that I have a fk to a user in both project and info. But the users are different, so I can't get rid of one. Is there a way to tell it that?

此外，我是全新的。NET，所以我希望这不是一个愚蠢的问题。我来自一个Django的背景下，如果与解释帮助。

Again, I am brand new to .net, so I'm hoping this isn't a silly question. I come from a django background, if that helps with explanation.

code：

public class Information
{

    [HiddenInput(DisplayValue = false)]
    public int InfoID { get; set; }

    //user
    public virtual User User { get; set; }
    [Required(ErrorMessage = "This field is required.")]
    public int UserID { get; set; }

    //project
    public virtual Project Project { get; set; }
    [Required(ErrorMessage = "This field is required.")]
    public int ProjectID { get; set; }

}

public class Project
{
    [HiddenInput(DisplayValue = false)]
    public int ProjectID { get; set; }

    //user
    public virtual User User { get; set; }
    [Required(ErrorMessage = "This field is required.")]
    public int UserID { get; set; }

}

予除去所有其它的非关系字段，这是因为它们并不重要。

I removed all of the other non-relational fields, since those are not important.

答

用户名需要两个实体和 ProjectID 需要信息实体。这将创建多个级联路径，如果你删除用户。 用户 - > 信息和用户 - > 项目 - > 信息

UserID is required for both entities and ProjectID is required for Information entity. This will create multiple cascading paths if you remove a User. User -> Information and User -> Project -> Information.

您必须使用流利的API映射关系，并指定用于至少一个关系，即 WillCascadeOnDelete（假）

You have to map the relationships using Fluent API and specify for atleast one relationship that WillCascadeOnDelete(false)

public class MyContext : DbContext
{
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<User>()
                    .HasMany(u => u.Informations)
                    .HasRequired(i => i.User)
                    .HasForeignKey(i => i.UserID)
                    .WillCascadeOnDelete(false);
    }
}

.NET MVC循环引用问题，实体

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