LINQ 到实体框架 - 级联删除 - 错误

Question

I have two related tables like this:

Users

 public partial class Users
    {
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
        public Users()
        {
            this.Orders = new HashSet<Orders>();
        }
    
        public int ID { get; set; }
        public int UserType_ID { get; set; }
        public string Email { get; set; }

    
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
        public virtual ICollection<Orders> Orders { get; set; }
        public virtual UserTypes UserTypes { get; set; }
    }

Oders

 public partial class Orders
    {
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
        public Orders()
        {
            this.Payments = new HashSet<Payments>();
        }
    
        public int ID { get; set; }
        public int User_ID { get; set; }
        public int Plan_ID { get; set; }
        public System.DateTime Date { get; set; }
        public int OrderStatus_ID { get; set; }
    
        public virtual OrderStatus OrderStatus { get; set; }
        public virtual Plans Plans { get; set; }
        public virtual Users Users { get; set; }
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
        public virtual ICollection<Payments> Payments { get; set; }
    }

Now i want force entity framework to cascade delete user rows.
Here is codes for delete a user:

using (Crypto_Shuffler_Entities entities = new Crypto_Shuffler_Entities())
{
    var users = from User in entities.Users
                where User.Email.ToLower() == "test@gmail.com"
                select User;
    entities.Users.Remove(users.FirstOrDefault());
    entities.SaveChanges();
}

An here is error:

An error occurred while updating the entries. See the inner exception for details.

Message = "The DELETE statement conflicted with the REFERENCE constraint "FK_Orders_Users". The conflict occurred in database "Crypto_DB", table "dbo.Orders", column 'User_ID'.\r\nThe statement has been terminated."

How force entity framework for cascade delete?

Answer 1

i think you need to remove first ref of users like in orders here one to many relation so according to my opinion first remove users in order and then save it to db and after that remove this user's row this may not be conflict