可以使用数据注释来执行使用实体框架4.1 RC的级联删除吗？ [英] Can I use Data Annotations to perform a Cascade Delete with Entity Framework 4.1 RC?

问题描述

当使用EF4.1 RC的数据注释时，是否有注释导致级联删除？

  public class Category 
 {
 public int Id {get;组; 
 [必需] 
 public string Name {get;组; } 
 public ICollection< Product>产品{get;组; } 
} 
 
 public class Product 
 {
 public int Id {get;组; } 
 public string Name {get;组; } 
 public Category Category {get;组; } 
} 
  

使用此模型生成的约束是：

  ALTER TABLE [Product] ADD CONSTRAINT [Product_Category] ​​
 FOREIGN KEY（[Category_Id]）参考[Categorys]（[Id]）
更新无更新行动; 
  

如果不是如何实现？

解决方案

在产品表上放置所需的类别关系字段解决这个

  public class Product 
 {
 public int Id {get;组; } 
 public string Name {get;组; } 
 
 [必需] //< =======强制级联删除
 public Category Category {get;组; } 
} 
  

When using data annotations with EF4.1 RC is there an annotation to cause cascade deletes?

public class Category
{
    public int Id { get; set; }
    [Required]
    public string Name { get; set; }
    public ICollection<Product> Products { get; set; }
}

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    public Category Category { get; set; }
}

Using this model the constraint generated is:

ALTER TABLE [Product] ADD CONSTRAINT [Product_Category] 
FOREIGN KEY ([Category_Id]) REFERENCES [Categorys]([Id]) 
ON DELETE NO ACTION ON UPDATE NO ACTION;

If not how is it achieved?

解决方案

Putting required on the Product table Category relationship field solves this

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }

    [Required]  //<======= Forces Cascade delete
    public Category Category { get; set; }
}

这篇关于可以使用数据注释来执行使用实体框架4.1 RC的级联删除吗？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！