我是pretty的新MVC和我遇到的麻烦与级联删除。对于我的模型我以下2类:
I'm pretty new to MVC and i'm having troubles with cascade deleting. For my model I the following 2 classes:
public class Blog
{
[Key]
public int Id { get; set; }
[Required]
public string Name { get; set; }
[DisplayFormat()]
public virtual ICollection<BlogEntry> BlogEntries { get; set; }
public DateTime CreationDateTime { get; set; }
public string UserName { get; set; }
}
public class BlogEntry
{
[Key]
public int Id { get; set; }
[Required]
public string Title { get; set; }
[Required]
public string Summary { get; set; }
[Required]
public string Body { get; set; }
public List<Comment> Comments { get; set; }
public List<Tag> Tags { get; set; }
public DateTime CreationDateTime { get; set; }
public DateTime UpdateDateTime { get; set; }
public virtual Blog ParentBlog { get; set; }
}
和我的控制器我把他删除后的下背部:
And for my controller I set he following on delete post back:
[HttpPost, ActionName("Delete")]
public ActionResult DeleteConfirmed(int id)
{
Blag blog = db.Blogs.Find(id);
foreach (var blogentry in blog.BlogEntries)
{
//blogentry = db.BlogEntries.Find(id);
db.BlogEntries.Remove(blogentry);
}
db.Blogs.Remove(blog);
db.SaveChanges();
return RedirectToAction("Index");
}
问题是,它不会工作,不管是什么; I阅读这篇文章但我似乎只工作模式,其中的关系是一一对应的,所以我在这里失去了,我有搜索无处不在,找不到这个问题的解决方案,如果有的可以点什么我失踪那将是非常好的:),在此先感谢,并再次,原谅我nooobness我刚开始起步,但要解决的一个大项目,以便能够学到很多东西。
Problem is it wont work no matter what; I read this post but i seem to only work for models where the relation is one to one, so i'm lost here, i have search everywhere, and can't find the solution for this problem, if some could point out what i'm missing it would be really nice :), thanks in advance, and again, pardon my nooobness i'm just getting started, but wanted to tackle a big project to be able to learn a lot.
这是因为EF在默认情况下不强制执行级联删除可选的关系。在模型中的关系推断为可选。
That is because EF by default does not enforce cascade deletes for optional relationships. The relationship in your model is inferred as optional.
您可以添加一个不为空的标量属性(BlogId )的FK的
You can add a non nullable scalar property(BlogId
) of the FK
public class BlogEntry
{
[Key]
public int Id { get; set; }
[Required]
public string Title { get; set; }
[Required]
public string Summary { get; set; }
[Required]
public string Body { get; set; }
public List<Comment> Comments { get; set; }
public List<Tag> Tags { get; set; }
public DateTime CreationDateTime { get; set; }
public DateTime UpdateDateTime { get; set; }
public int ParentBlogId { get; set; }
public virtual Blog ParentBlog { get; set; }
}
或配置此用流利的API
Or configure this using fluent API
modelBuilder.Entity<BlogEntry>()
.HasRequired(b => b.ParentBlog)
.WithMany(b => b.BlogEntries)
.WillCascadeOnDelete(true);