Force child class to implement private method

Question

I have the following code:

public abstract class NavEntityController<ChildEntity> where ChildEntity : NavObservableEntity
{
    public abstract void Delete(ChildEntity line);
    public abstract void Update(ChildEntity line);
    public abstract void Create(ChildEntity line);

    public void PushChangesToNav(NavObservableCollection<ChildEntity> lines) 
    {
        foreach (var line in lines)
        {
            line.ErrorLastAction = false;
            EntityState previousState = line.CurrentState;

            try
            {
                switch (line.CurrentState)
                {
                    case EntityState.Unchanged:
                        break;
                    case EntityState.NeedsCreate:
                        Create(line);
                        line.CurrentState = EntityState.Unchanged;
                        break;
                    case EntityState.NeedsUpdate:
                        Update(line);
                        line.CurrentState = EntityState.Unchanged;
                        break;
                    case EntityState.NeedsDelete:
                        Delete(line);
                        line.CurrentState = EntityState.Deleted;
                        break;
                }
            }
            catch (Exception e)
            {
                //...
            }        
        }
    }
}

I need a base class to inherit from this class, like such:

public class NavJobController : NavEntityController<NavObservableJob>
{
    public NavJobController( {}

    public override void Delete(NavObservableJob line) {//Implementation here}
    public override void Update(NavObservableJob line) {//Implementation here}
    public override void Create(NavObservableJob line) {//Implementation here}

    //Other functionality
}

However, I do not want someone to be able to do:

NavJobController j = new NavJobController();
j.Create(new NavObservableJob());

but only would like the following method:

j.PushToNav(); //and any other public functionality in the base class to be available

Essentially, I want to force the child class to implement CRUD operations, without exposing them to the public. The ideal syntax I was hoping for is the following:

private abstract void Delete(ChildEntity line);
private abstract void Update(ChildEntity line);
private abstract void Create(ChildEntity line);

Answer 1

This is why protected visibility exists (visible to both base class and derived classes, but not publicly available to use them from an instance).

If you need to publicly access these methods somewhere in your solution, you may need to use internal instead of protected and make internals visible to some assemblies using [InternalsVisibleTo] attribute.