EF Code First cascade delete and update?

问题

My entities are these:

public class Customer
{
    public Customer()
    {
        Invoices = new List<Invoice>();
        Payments = new List<Payment>();
    }

    public int ID { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }

    public IList<Payment> Payments { get; set; }
}

public class Payment
{
    public int ID { get; set; }
    public int CustomerID { get; set; }
    public decimal CreditPrice { get; set; }
    public decimal DebitPrice { get; set; }
    public DateTime PaymentDate { get; set; }

    [ForeignKey("CustomerID")]
    public Customer Customer { get; set; }
}

and this is my context:

public class AccountingContext : DbContext, IDisposable
{
    public DbSet<Customer> Customers { get; set; }
    public DbSet<Payment> Payments { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();

        modelBuilder.Entity<Payment>()
                .HasRequired(s => s.Customer)
                .WillCascadeOnDelete();

        base.OnModelCreating(modelBuilder);
    }
}

i get this error in WillCascadeOnDelete():

Error 1 'System.Data.Entity.ModelConfiguration.Configuration.RequiredNavigationPropertyConfiguration' does not contain a definition for 'WillCascadeOnDelete' and no extension method 'WillCascadeOnDelete' accepting a first argument of type 'System.Data.Entity.ModelConfiguration.Configuration.RequiredNavigationPropertyConfiguration' could be found (are you missing a using directive or an assembly reference?) D:\Work\C# Projects\Visual Studio 2010\Windows\WPF\New folder\Accounting Without EF Code First\Accounting - Copy\DAL.EF.CodeFirst\Entities\Context\AccountingContext.cs 22 22 DAL.EF.CodeFirst

i want to delete payments of the customer cascading (Just if customer getting deleted). how can i achieve this in EF code first?

also i want to use cascade update. please help me in these issues. thanx.

回答1:

Description

You need to configure the modelBuilder in your context.

Sample

public class AccountingContext : DbContext, IDisposable
{
    public DbSet<Customer> Customers { get; set; }
    public DbSet<Payment> Payments { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();

        modelBuilder.Entity<Payment>()
                .HasRequired(s => s.Customer)
                .WithMany()
                .WillCascadeOnDelete(true);

        base.OnModelCreating(modelBuilder);
    }
}

来源：https://stackoverflow.com/questions/10523291/ef-code-first-cascade-delete-and-update