How to configure a One-to-Many relationship in EF

Question

I have the following model

public class PageConfig : Base
{
    // Properties Etc..

    public ICollection ScrollerImages { get; set; }
}
         


        

Answer 1

Per http://www.entityframeworktutorial.net/code-first/configure-one-to-many-relationship-in-code-first.aspx:

"...you can use Fluent API to configure a One-to-Many relationship using Student entity classes as shown below."

protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
            //one-to-many 
            modelBuilder.Entity()
                        .HasRequired(s => s.Standard)
                        .WithMany(s => s.Students)
                        .HasForeignKey(s => s.StdId);

    }

"...Use HasOptional method instead of HasRequired method to make foreign key column nullable."

So you'd be looking for something like this:

modelBuilder.Entity()
            .HasOptional(x => x.PageConfig)
            .WithMany(x => x.ScrollerImages)
            .HasForeignKey(x => x.PageConfigId)