How can I have Entity Framework return related objects with some defaults?

Question

Say I have Project and Task EF Code first classes

public class Project
    {
        public int ID { get; set; }
        public string Name { get; set; }
        public virtual ICollection<Task> Tasks { get; set; }
    }

    public class Task
    {
        public int ID { get; set; }
        public string Name { get; set; }
        public int ProjectId { get; set; }
        public bool IsDeleted {get; set;}
        public virtual Project Project { get; set; }
    }

Say I have

public void SomeAction()
{
Project p= repository.GetById(1);
var tasks = p.Tasks;
//var tasks = p.Tasks.Where(t=>t.IsDeleted==false);
}

I would like that my Tasks property on the Project class will always perform that filter on IsDeleted and just return that subset ... to avoid having to write that condition all over the place...

Any recommendations?

Edit:

Im using EF Code First

Answer 1

Add a discriminator to your model in the OnModelCreating method

modelBuilder.Entity<TEntity>().Map(m => m.Requires("IsDeleted").HasValue(false));

Caveats

• You can no longer load deleted items (unless you map IsDeleted true to another entity, then you may lose your automatic filtering)
• The poco class cannot have the IsDeleted property (discriminators cannot be mapped)
• because the IsDeleted cannot be mapped you need to run raw SQL to delete the entity in the first place.