在插入此代码时,我在代码优先 MVC CORE 中收到此错误,并且我正在为第一个 Time 命令执行代码优先:
Update-Database -Context ProjectDbContext
“在表 'Product' 上引入 FOREIGN KEY 约束 'FK_Product_SubCategory_SubCategoryId' 可能会导致循环或多个级联路径。指定 ON DELETE NO ACTION 或 ON UPDATE NO ACTION,或修改其他 FOREIGN KEY 约束”。
下面给出了我的类,并解释了为什么我们在 mvc 模型类中使用关联,如下所示:
public virtual SubCategory SubCategory { get; set; }
Or
public virtual ICollection<Category> Category { get; set; }
public virtual Icollection<SubCategory> SubCategory { get; set; }
public class Product
{
public int ProductId { get; set; }
[Required]
public string ProductName { get; set; }
[Required]
public string ProductModel { get; set; }
[Required]
public int Quatity { get; set; }
[Required]
public int Price { get; set; }
[Required]
public string Description { get; set; }
[Required]
public string ProductColor { get; set; }
public byte Status { get; set; }
public DateTime TodayDate { get; set; }
[Required]
public int CategoryId { get; set; }
[Required]
public int SubCategoryId { get; set; }
public virtual Category Category { get; set; }
public virtual SubCategory SubCategory { get; set; }
}
public class SubCategory
{
public int SubCategoryId { get; set; }
[Required]
public string SubCategoryName { set; get; }
[Required]
public int CategoryId { get; set; }
public ICollection< Category> Category { set; get; }
public ICollection<Product> Product { set; get; }
}
public class Category
{
public int CategoryId { set; get; }
[Required]
public string Name { get; set; }
}